dr gregor
Are Vegans at Risk for Iodine Deficiency?
"Are Vegans at Risk
for Iodine Deficiency?" Adequate dietary iodine is required
for normal thyroid function. In fact, the two thyroid hormones
are named after how many iodine atoms they
contain: T3 and T4. Now, given that iodine is extensively
stored in the thyroid gland itself, it's not something you
have to get every day, but your overall diet needs
to have some good source. Unfortunately, the common sources
aren't particularly health-promoting: iodized salt, [and] dairy foods because iodine-based cleansers
like betadine are used to sanitize the udders, which results in some
iodine leaching into the milk.
They also add iodine to cattle feed, and some commercial breads have
iodine-containing food additives. So if you put people on a paleo-type
diet and cut out dairy and table salt, they can develop an iodine deficiency,
even though they double their seafood intake, which
can also be a source. What about those switching to diets
centered around whole plant foods? They're also cutting down
on ice cream and Wonder Bread, and if they're not eating anything from
the sea—seaweed, sea vegetables— they can run into the same problem. Her parents reported striving to
feed her only the healthiest foods. The 3-year-old only got plant-based,
unsalted, unprocessed foods with no vitamin supplementation.
Now that could have been deadly.
With no vitamin B12, those on strictly
plant-based diets can develop irreversible nerve damage, but
in this case, a goiter arose first due to inadequate iodine intake. Here's another case of veganism
as a cause of iodine deficient hypothyroidism in a toddler after
weaning. Now before weaning, he was fine because his mother
kept taking her prenatal vitamins, which luckily contained iodine. Most vegetarians and vegans are
apparently unaware of the importance of iodine in pregnancy, just as clueless
as their omnivorous counterparts. The American Thyroid Association and
the American Academy of Pediatrics have recommended that women even
just planning on getting pregnant should ingest a daily supplement that
contains 150 micrograms of iodine, yet only 60% of prenatal vitamins marketed
in the US contain this essential mineral. So, in spite of the recommendations,
about 40% lack it. Therefore, it's extremely important that pregnant and
breastfeeding women read the labels to ensure they're receiving
an adequate amount. Women of reproductive age have
an average iodine level of 110, which is fine for nonpregnant
individuals, but we'd really like to see at least
150 in pregnancy. It's basically a 24-hour urine test,
in which iodine sufficiency is defined as 100 mcg/liter of pee in nonpregnant
adults, which your average vegan fails to reach in the largest study
done to date, out of Boston.
The recommended average daily
intake is 150 mcg/day for most people, which you can get in like a
cup and a half of cow's milk. Sadly, plant-based milks are
typically not fortified with iodine, averaging only about 3 mcg/cup.
In the largest systematic study to date, although many plant-based milks are
fortified with calcium, they only found just 3 of 47 fortified with iodine. Those that were had as much as cow's
milk, but those that weren't fell short. Plant-based milk companies brag about
enriching their milks with calcium, and often vitamin B12, D, and vitamin A,
but only rarely are attempts made to match the iodine content. The only reason cow's milk has as
much as it does is that they enrich the feed, or it comes
dripping off their udders. So why don't plant-milk
companies add iodine, too? I was told by a food scientist at
Silk that my carrageenan video played a role in them
switching to another thickener. Hopefully, they'll see this video
and consider adding iodine, too, or some company will snatch at
the market advantage opportunity.
The researchers conclude that individuals
who consume plant-based milks not fortified with iodine may be
at risk for iodine deficiency, unless they consume alternative
dietary iodine sources, the healthiest of which is sea
vegetables, which we'll cover next..
Video Transcript – As found on YouTube
Improving VO2 Max: A Look at Vegetarian and Vegan Athletes
This is the first of a three
video series about exercise. Do plant based diets have an
impact on fitness? What are the best times
to workout? Watch the series to find out. "Improving VO2 Max: A Look
at Vegetarian and Vegan Athletes" In my video about comparing vegetarian
and vegan athletic performance, endurance, and strength, I discussed
a 2020 study that found that vegan athletes—even though
they were significantly older— had significantly superior
aerobic capacity and endurance, lasting 25 percent longer on a
time-to-exhaustion cycling test. The question is why? One potential mechanism
that could explain the greater level of endurance performance
in vegans may be a higher amount of carbohydrate intake, which could
lead to better endurance performance through higher
muscle glycogen storage. Other potential mechanisms
that may explain the better endurance performance in vegans could
be due to the anti-oxidant and anti-inflammatory
profiles of their diet. Maybe it’s even their hearts. Yet another study showing superior
VO2 max in vegan athletes, meaning superior
aerobic capacity: this time they also
did echocardiograms, looking at their hearts
in real-time using ultrasound, and the lower relative
wall thickness and better main ventricle
systolic and diastolic function in the vegans are most
likely positive findings.
Now wait a second. Given
the higher VO2 max reached by the vegan athletes, maybe
they were just better trained than the nonvegan athletes,
and that’s why their hearts looked like they
were working better. However, the weekly training
frequency and running distance were similar in both groups,
suggesting benefits even with the same
amount of training. So, it’s important to educate
healthcare professionals; so they don’t try
to discourage a vegan diet and may even want to consider
telling folks implementing an exercise training
program to give it a try. But you don’t know if it
has the same kinds of effects in nonathletes, until
you…put it to the test. A vegetarian vs. conventional
calorie-restricted diet: the effect on physical fitness
in response to aerobic exercise in patients with
type 2 diabetes.
Diabetics were randomized
to the same caloric restriction, the same exercise, but just
vegetarian versus nonvegetarian. They provided all the meals
so they could ensure compliance and closely monitored
the exercising. VO2 max increased by 12 percent
in the vegetarian group, significantly better than in
the non-vegetarian group who didn’t significantly
improve at all. Maximal performance increased
by 21 percent in the vegetarian group, again, significantly better than in
the non-vegetarian group who didn’t significantly
improve at all. In other words, the results indicated
that more plant-based diets led more effectively to
improvement in physical fitness than less plant-based diets, after the same aerobic
exercise program.
Here’s what the graphs look like: significantly better power
output and aerobic capacity in the group that was randomized
to a vegetarian diet. It seems that those eating vegetarian were able to better burn off carbohydrates compared
to nonvegetarians, and had better insulin sensitivity, both markers of improved
metabolic flexibility, meaning the ability
to switch back and forth between burning sugar and fat. Besides physiological
mechanisms, there may also be
psychological factors. They observed reduced hunger
and reduced feelings of depression in the vegetarian group
which may have given them a more positive attitude
towards exercise. Here’s the psychological data. Those randomized to eat vegetarian
had a greater improvement in quality of life and mood. They felt less constrained,
meaning the calorie restriction didn’t seem as burdensome; they had less disinhibition, meaning less tendency
to binge and overeat, along with maybe
less feelings of hunger. Not to mention the superior effects
of a vegetarian diet on body weight, glycemic control,
blood lipids, insulin sensitivity,
and oxidative stress.
Wait, better body weight? I thought they were given
the same number of calories. Yes, both diets were isocaloric,
the same calories, yet just eating meat-free led
to significantly more weight loss— about six pounds more;
more waist loss, a slimmer waist; lower cholesterol, of course;
and less superficial fat, meaning the external jiggly fat; and most importantly, significantly
more visceral fat loss, the most metabolically
dangerous deep belly fat. Same calories, yet more
loss of body fat. And not surprisingly,
better control of their diabetes. All in addition to leading
more effectively to improvements
in physical fitness..
Video Transcript – As found on YouTube
Potential Vitamin and Mineral Deficiency Risks on a Vegan Diet
"Potential Vitamin and Mineral
Deficiency Risks on a Vegan Diet" The "Vegan Diet as a Neglected
Cause of Psychosis" A tragic story of a 47-year-old woman
with a 5-year history of psychosis, treated with antipsychotics,
years of hallucinations. Finally her mother revealed
that the patient was following a strict vegan diet for 7 years
and was not supplementing with vitamin B12. They started giving her B12
supplements and eventually her psychiatric symptoms went away.
But she spent 5 years of her life in a psychotic haze
because she wasn't getting a regular reliable source
of vitamin B12. B12 supplements, or sufficient
intake of B12-fortified foods, is mandatory for vegans — and
effective, but only if you do it. Like in the largest study of vegans
in history, the Adventist-2 study, the prevalence of low vitamin
B-12 status was the same between vegans, vegetarians,
and meat-eaters.
Why? Presumably because they were eating fortified
foods and supplements. The researchers concluded the
encouragement of vitamin B-12 supplementation cannot
be overemphasized. Vitamins B12 and D are the only
two vitamins not made by plants. B12 is made by microbes, and
vitamin D is made by animals — such as ourselves when we walk
outside; it's the sunshine vitamin. Some other nutrients are
only found concentrated in certain plants though. You can become deficient
if you don't eat them. For example, this case
of a 10-year-old girl with night blindness.
She couldn't see well at night. Vitamin A deficiency was
the doctor's first thought, but the kid was vegetarian
and so getting whopping doses of beta carotene in all
the vegetables she ate, which your body turns
into vitamin A. Almost as an afterthought as
they were leaving the office, the doctor just asked the mother, "I assume she is getting
plenty of vegetables, right?" But no, she does not like vegetables
and only eats like, I don't know, Ritz
crackers or something.
So with something like vitamin A,
it's easy getting enough eating greens or any of the orange
fruits and vegetables like mangos, sweet potatoes, carrots,
or cantaloupe, but you actually have to
eat fruits and vegetables. A vegan living off a diet
of fast food is at a greater risk for vitamin A deficiency than
a meat eater living on fast food because at least the cow ate
some greens and passed it along.
Iodine is a similar situation. Cow's milk is a primary source of
dietary iodine in the United States, not because cows somehow synthesize
iodine or any other element. Iodine in milk comes from the leaching
of iodine-containing disinfectants used to clean contaminated udders
and milking equipment into the milk, or from supplements fed to cattle. Regardless, those not drinking
milk or eating seaweed — which is even a better source — may be at increased risk
for iodine deficiency. A study of vegans in the UK
suggested as many as 90% aren't getting enough
in their diet, though this is likely
an overestimate since their food frequency
questionnaire didn't include seaweed or iodized salt, two of
the ways some may be getting it. Are there reports of it
actually causing problems? Yes, indeed: "Veganism as a cause of
iodine deficient hypothyroidism" A 23-month-old boy, breastfed
until 16 months of age, then weaned on a strictly plant-based
diet without iodized salt. Mom was fine, presumably because
of the iodine in her prenatal vitamins that she continued to take, which
spilled over into her breastmilk. The American Thyroid Association
is very clear about recommending that pregnant and breastfeeding
women take a prenatal with 150 micrograms
of iodine a day.
Most kids in the U.S. transition
from breast milk to cow's milk, but those who don't need to get
their iodine from somewhere. Thankfully after an iodine-containing
multivitamin, his deficiency cleared. That's one way, taking
supplements like the cows do, but sea vegetables are the
healthiest source of iodine. A half teaspoon of mild
seaweeds like arame or dulse should get you all the iodine
you need for the day. You can just have a shaker of
dulse flakes at the kitchen table, or two nori sheets of seaweed. That's my favorite method because
you can just eat them like a snack — in fact probably the healthiest
snack since you're snacking on dark green leafy vegetables.
There was also a recent report
of severe iron-deficiency anemia attributed to a plant-based
diet and menorrhagia, which means excess blood
loss during menstruation. A 21-year-old woman presented with
reduced vision in one of her eyes because a vein clotted off,
which can happen when you get really anemic. Thankfully her vision resolved
after taking iron supplements. Now according to the
American Dietetic Association, the incidence of iron-deficiency
anemia among vegetarians is no worse than
that of nonvegetarians, so it may just have been her
excess monthly blood loss. But a more recent review
questioned the official position that iron deficiency anemia appears
no more prevalent among vegetarian women than
among nonvegetarian women. The updated review claimed
to find four studies where this wasn't the case, where vegetarians had
significantly higher rates. Yet, here's the four studies — and as always, I'll put links
to them in the sources cited section beneath this video
on NutritionFacts.org so you can read them yourself, like I do for every study
I cite in my videos — and not a single one
backed up that statement.
But just because vegetarians
don't have worse anemia rates than nonvegetarians, that's not
saying much since up to 1 in 20 menstruating women suffer
from iron-deficiency anemia across the board. Having lower iron stores
is actually advantageous — as I've done videos about — yet another reason to consume
more plants and less meat. But if your blood count
is dropping, if your hemoglobin is getting too low, then you
can enhance iron absorption by eating vitamin C rich foods with your meals, so fresh fruit,
bell peppers, broccoli, etc. And since especially tea,
but also coffee, can inhibit iron absorption, you
shouldn't drink them with meals..
Video Transcript – As found on YouTube
How to Lower Heavy Metal Levels with Diet
"How to Lower Heavy Metal
Levels with Diet" We’ve previously explored the issue of lead contamination in calcium supplements like bone meal, but it wasn’t just bone meal. Substantial quantities of lead were found in other, more common, over-the-counter supplements. Still, testing revealed continued public health concern over bone meal, but thankfully it’s not
as popular these days. So, many of us are not likely to get directly exposed to the lead in bone meal any more – but may get indirectly exposed through the animals we eat. In the U.S., five billion pounds of meat and bone meal are produced as slaughterhouse by-products every year. What do we do with these millions of tons every year? We feed it back to farm animals, particularly chickens. Now, most of the lead in the bone meal passes right through the animals into their waste, but then we take that waste (cow, pig, and chicken feces) and feed it back to the animals again. You guessed it! So, you can see how the levels of contaminants might
buildup in their body.
I’ve talked previously about
what that might mean for making something like chicken soup, but the original concern about these kinds of feeding practices, of feeding cows to cows,
and pigs and chickens, was the spread of prion diseases, like mad cow disease, but it’s not just prions that this kind of recycling can magnify; but other toxic substances including lead. So, a more plant-based diet may be able to lower lead exposure, and an even more plant-based diet could theoretically lower
exposure even more, but you’ve got to put it to the test. But, should we expect to find a benefit? Yes, lead is one of the
toxins found in meat, but half of our dietary exposure probably comes from plant foods.
Dietary modeling studies in Europe suggest that vegetarians would be exposed to about the same amount of lead compared to
the general population, with the exception of those who eat a lot of wild game, which can end up with a thousand times more lead than most other foods. In fact, a vegetarian diet
may even be higher in lead. But, it’s not what you eat; it’s what you absorb. As we learned from the cadmium story, the uptake of toxic heavy metals from animal food sources into the human intestinal lining cells may be higher than that from vegetable sources. That’s how you have a vegetarian with some of the lowest concentrations of lead and cadmium in her blood, despite higher concentrations in her diet. But you don’t know, until you… put it to the test.
There seemed to be a tendency towards higher fecal elimination of lead following a change to a vegetarian diet, with nine subjects on average tripling their elimination of lead, three unaffected, and four
dropping by about half. But, the study only lasted a few months; the difference wasn’t
statistically significant. So, let’s try a year. A shift towards a diet characterized by large amounts of raw vegetables, fruits, and unrefined foods, whole grains, with the exclusion of
meat, poultry, fish, and eggs (though it did include fermented dairy, like a type of soured milk), as well as cutting back on
processed foods and junk. They took clippings of hair before and after the shift, and got significant reductions
in heavy metals, including cutting their lead level nearly in half. Check this out: this is how much mercury, cadmium, and lead they had oozing from their body into their hair when they started, and within three months, their toxic heavy metals went down, and stayed down. How do we know it wasn’t just a coincidence? Because they went back up a few years later after the study was over, after they went back to more of their regular diet, and their mercury, cadmium, and lead levels shot back up to where they were before.
Same thing with a different
group after two years. The drop in mercury is easy to explain, presumably due to the drastic drop in fish consumption, and the drop in alcoholic beverages may have contributed to the drop in lead, but it also could have been a cadmium-like effect, where the decrease in hair lead content could be due to the dietary shift resulting in less absorption of lead into the body in the first place..
Video Transcript – As found on YouTube
How to Reverse Heart Failure with Diet
"How to Reverse Heart Failure with Diet" It is a hopeful sign of the times when
entire issues of cardiology journals are not just dedicated to nutrition,
but to plant-based diets in particular. Dr. Williams, past president of the
American College of Cardiology, starts out with a quote
attributed to Schopenhauer. "All truth passes through three
stages. First, it is ridiculed. Second, it is violently opposed. Third,
it is accepted as…" like, well, duh. And the truth for the benefits
of plant-based diets, plant-based nutrition
continues to mount. The evidence, we got; the problem
is the inertia, culture, habit, and widespread marketing of
unhealthy foods.
"Our goal must be to get the data out to the medical
community and the public where it can actually change lives…" That's like my personal life's mission
in four words: get the data out. Based on what we already know in the
existing medical literature, plant-based nutrition clearly represents the single
most important yet underutilized opportunity to reverse the pending
obesity and diabetes-induced epidemic of morbidity and mortality,
meaning disease and death.
The issue included your typical
heart disease reversal cases: a 77-year old woman with heart disease
so bad she couldn't walk more than a half-block or go up a single flight
of stairs, severe blockages in all three of her main arteries, and referred
to open heart surgery for a bypass. She chose, however, instead to
adopt a whole-food plant-based diet, which included all vegetables, fruits,
whole grains, potatoes, beans, legumes, and nuts. Even though she said she
was trying to eat pretty healthy before, within a single month of going plant-
based her symptoms had nearly resolved.
And forget about a block, she
was able to walk on a treadmill for up to 50 minutes without chest
discomfort or becoming out of breath. Her cholesterol dropped about a hundred
points from around 220 down to 120, with an LDL under 60. But then, a few months later she must
have started missing her chicken, fish, and low-fat dairy, and went back
to her prior eating habits. And within a few weeks, with no change
in her meds or anything, her chest pain was back, and she went on to have
her chest sawed in half after all. Then she continued to eat the same diet
that contributed to cause her disease in the first place and went on to
have further disease progression. This one, though, has a happier ending.
It started out the same: a 60-year-old man, severe chest pain
after as little as a half-block.
Decided to take control of his health
destiny and switched to a whole food plant-based diet from his "healthy" diet
of skinless chicken, fish, low-fat dairy that had been choking off his heart. And within a few weeks, the same
amazing transformation. From not being able to exercise
at all, to walking a mile, to then being able to jog more than
four miles, completely asymptomatic, off all drugs, no surgery,
off to live happily ever after. Now, of course, case reports are
just really glorified anecdotes. I mean, what we need is a randomized
controlled trial to prove heart disease can be reversed with lifestyle
changes alone.
And guess what? There was one, published literally
30 years ago, proving angiographic reversal of heart disease
in 82% of the patients, opening up arteries without
drugs, without surgery. So these case reports are just to
remind us that hundreds of thousands of Americans continue
to needlessly die every year from what was proven to be a
reversible condition decades ago. The conventional use of case reports,
though, is to present some novel results in hopes of inspiring trials
to put it to the test. For example, a case report on a plant-
based diet for congestive heart failure. So not just coronary artery disease, but
the heart muscle itself was so weakened it couldn't efficiently pump blood, only
able to eject about 35% of the blood in the main heart chamber with every
beat, whereas normally the heart can pump out at least half; which is
exactly what his heart was able to do just six weeks after switching to
a whole-food plant-based diet, instead of choosing to get
his chest cracked open.
The first report of an improvement
in heart failure following adoption of a plant-based diet, but not the last.
A 54-year-old woman, obese, type 2 diabetic, presenting with
swelling ankles due to her heart failure. She switched from her chicken
and fish to whole plant foods. She started out eating healthier and lost
50 pounds, reversed her diabetes— meaning normal blood sugars on
a normal diet without the use of diabetes medications—and
her heart function normalized, from an abysmal ejection fraction
of just 25% up to normal. Now since it's not a
randomized controlled trial, all we can say is
that her improvements coincided with her adoption of
a whole food plant-based diet. But given the burden of heart failure
as a leading cause of death, how it usually just gets progressively
worse, and the overall evidence to date, a plant-based diet should be
considered as part of heart failure care. And look, we already know it can
reverse her coronary artery disease, and so any heart failure
benefits would just be a bonus.
Now, we just need good strategies
for healthcare practitioners to support patients in plant-based eating. Here are some excellent suggestions
to pause and reflect on. For example, doctors can
use the Plantrician Project's prescription pads and
prescribe a good website or two. While it is certainly true that
many people would be resistant to fundamental dietary changes, look, it is equally true that
millions of intelligent people motivated to preserve their health
are now taking half-way measures that may provide only modest benefit—
choosing leaner cuts of meat, using reduced-fat dairy products.
Most of these people have neither the time nor the training to actually see
what the science shows themselves. Don't they deserve honest, forthright
advice when their lives are at stake? Those who wish to ignore that advice,
or implement it only partially, are certainly at liberty to do so. I mean, you want to go smoke
cigarettes, go bungie jumping? It's your body, your choice.
It's up to each of us to make our own decisions as to
what to eat and how to live.
But we should make these choices
consciously, educating ourselves about the predictable
consequences of our actions..
Video Transcript – As found on YouTube
Do Vegetarians Really Have Higher Stroke Risk?
"Do Vegetarians Really
Have Higher Stroke Risk?" When ranked in order of importance,
among the interventions available to prevent stroke, the three
most important are probably diet, smoking cessation, and
blood pressure control. Most of us are doing pretty
good on smoking these days, less than half of us are exercising
enough, but according to the American Heart Association only 1
in a thousand Americans are eating a healthy diet, and fewer than 1 in 10
are even eating a moderately healthy diet. Why does it matter? Because diet is an important
part of stroke prevention. Reducing sodium intake, avoiding egg
yolks, limiting the intake of meat, and increasing the intake of whole grains,
fruits, vegetables and lentils. Like the sugar industry, the meat
and egg industries spend hundreds of millions of dollars on propaganda,
unfortunately with great success. I was excited to check out Box number 1,
and was then honored, when I did. The strongest evidence for stroke
protection is for increasing fruit and vegetable intake, with
more uncertainty regarding the role of whole grains, animal products, and
dietary patterns such as vegetarian diets.
I mean one would expect they’d do great. Meta-analyses have found that
vegetarian diets lower cholesterol and blood pressure, and enhance
weight loss, and blood sugar control, and vegan diets may work even better.
So, all the key biomarkers are going in the right direction, but
you may be surprised to learn that there hadn’t ever been any
studies on the incidence of stroke in vegetarians and vegans… until, now. And if you think that's surprising,
wait until you hear the results. The risks of heart disease
and stroke in meat eaters, fish eaters, and vegetarians
over 18 years of follow-up.
Yes, less heart disease
among vegetarians (by which they mean vegetarians and vegans combined) no surprise—been there, done
that, but more stroke. An understandable knee-jerk
reaction might be “Wait a second, who did this study?” But this is EPIC-Oxford, world-class
researchers whose conflicts of interest may be more likely to read “I was
a member of the Vegan Society.” What about overadjustment? If you crunch the numbers
over a ten-year-period they found 15 strokes for every thousand
meat-eaters compared to only 9 strokes for every thousand
vegetarians and vegans.
Wait, so how can they say there
were more strokes in the vegetarians? This was after adjusting
for a variety of factors. For example, the vegetarians
were less likely to smoke; so, you want to cancel that
out by adjusting for smoking, so that you can effectively
compare the stroke risk of nonsmoking vegetarians
to nonsmoking meat-eaters. If you want to know how a vegetarian
diet itself affects stroke rates, you want to cancel out these
non-diet-related factors. Sometimes, though, you can overadjust. The sugar industry does it all the time. This is how it works. Imagine you just got a grant
from the soda industry to study the effect of soda on
the childhood obesity epidemic.
What could you possibly do after
putting all the studies together to arrive at the conclusion that
there was near zero effect of sugary beverage consumption
on body weight? Well, since you know that
drinking liquid candy can lead to excess calories that can lead
to obesity, if you control for calories, if you control for a factor
that’s in the causal chain, effectively only comparing soda
drinkers who take in the same number of calories as non-soda-drinkers
then you could undermine the soda-to-obesity effect, and
that’s exactly what they did. That introduces overadjustment bias. Instead of just controlling
for some unrelated factor, you control for an intermediate
variable on the cause-and-effect pathway
between exposure and outcome. Overadjustment is how meat-and-
dairy industry funded researchers have been accused of obscuring
the true association between saturated fat and cardiovascular disease. We know that saturated
fat increases cholesterol which increases heart disease risk. Therefore, if you control for
cholesterol, effectively only comparing saturated fat eaters with the
same cholesterol levels as non-saturated-fat eaters,
you see how you could undermine the saturated fat-to-heart disease effect.
Now let’s get back to this. Since vegetarian eating
lowers blood pressure, and a lowered blood pressure
leads to less stroke, controlling for blood pressure would be an
overadjustment, effectively only comparing vegetarians to meat-eaters
with the same low blood pressure. That’s not fair, since that’s one
of the benefits of vegetarian eating, not some unrelated factor like smoking; and so, it would undermine
the afforded protection. So, did they do that? No. They only adjusted for unrelated factors, like education, and socioeconomic class,
and smoking, and exercise, and alcohol. That’s what you want. You want to tease out the effects of a vegetarian diet on stroke risk…
you want to try to equalize everything else to tease out the
effects of just the dietary choice.
And since, for example, meat eaters
in the study were on average 10 years older than the vegetarians,
you can totally see how when you adjust for that
vegetarians could come out worse. Since stroke risk can increase
exponentially with age, you can see how having 9 strokes among
a thousand vegetarians in their 40s could be worse than 15 strokes among
a thousand meat-eaters in their 50s. The fact that vegetarians had
greater stroke risk despite their lower blood pressure suggests
there’s something about meat-free diets that so increases stroke risk it’s enough
to cancel out the blood pressure benefits, but even if that’s true you
still would want to eat that way. Stroke is our 5th leading cause of
death, whereas heart disease is #1. So, yes, in this study there
were this many more cases of stroke in vegetarians, but there were this many
fewer cases of heart disease, but if there is something increasing
stroke risk in vegetarians it would be nice to know what
it is in hopes of figuring out how to get the best of both worlds.
This is the question we'll turn to, next..
Video Transcript – As found on YouTube
Is Vegan Food Always Healthy?
"Is Vegan Food Always Healthy?" In my video on flexitarians,
I talk about how the benefits of eating a plant-based diet
are not all-or-nothing. Simple advice to increase
the consumption of plant-derived foods with
parallel reductions in the consumption of foods from
animal sources was found to confer a survival advantage,”
a live-longer advantage. They call it a pro-vegetarian eating
pattern, just moving in that direction, as a more gradual, gentle
doable approach. If you’re dealing with a serious
disease, though, like diabetes, avoiding some problem foods
completely may be easier than attempting to moderate their intake. It’s like clinicians would never tell
alcoholics to simply cut down on alcohol. Avoiding alcohol entirely
is a more effective and, ironically, easier for a problem drinker. Paradoxically, asking patients
to make a large change may be more effective than
making a slow transition. Diet studies show that recommending
more significant changes increases the changes that
patients actually accomplish.
It may help to replace the common
advice, ‘all things in moderation’ with ‘big changes beget big results.’ Success breeds success. After a few days or weeks of
major dietary changes, patients are more likely
to see improvements in weight and blood sugar levels— improvements that
reinforce the dietary changes. Furthermore, they may enjoy other health
benefits of plant-based eating. that may give them further motivation. Those who choose to eat plant-based
for their health say it’s mostly for general wellness and disease
prevention, or to improve their energy levels or immune function.
They felt it gave them a sense
of control over their health, helps you feel better emotionally,
improves your overall health, and makes you feel better. Most felt it was very important for
maintaining their health and well-being. For the minority that used it
for a specific health problem, it was mostly for high cholesterol
or weight loss, followed by high blood pressure
and diabetes, with most reporting they felt it helped a great deal. But others choose plant-based diets
for other reasons like animal welfare or global warming, and it looks
like they’re more likely to be eating things like vegan doughnuts,
sugary and fatty foods, compared to those eating
plant-based because of religious or health reasons. I mean the veganist vegan could bake
a cake using soda instead of eggs, with frosting, covered in marshmallow
fluff and chocolate syrup, topped with Oreos, with a side of Doritos
dipped in, vegan bacon grease.
But fruit for dessert… in the form of
Pop Tarts and Krispy Kreme pies. This, is a vegan meal. Yes, plant-based diets have
been recommended to reduce the risk of type 2 diabetes. However, not all plant foods
are necessarily beneficial. Like in that pro-vegetarian scoring
system you got points for eating potato chips and French fries,
just because they were technically plant-based, but Harvard researchers
wanted to examine the association of not only an overall plant-based diet,
but both healthy and unhealthy versions. So, they created the same kind
of pro-vegetarian scoring system weighted towards any sort
of plant-based foods, and against animal foods and then also
created a healthful plant-based diet index, where at least some whole
plant foods took precedence and Coca-Cola was no longer
considered a plant. Then lastly, they created an
unhealthful plant-based diet index by assigning positive scores
to processed plant-based junk, and negative scoring healthier
foods and animal foods. And then they found that a more
plant-based diet in general was good for reducing diabetes risk, but eating
especially healthy plant-based foods did better, nearly cutting risk in half, while those eating more
unhealthy plant foods did worse.
Now, but is that because they
were also eating more animal foods? People often eat burgers with their fries; so, they separated out the
effects of healthy plant foods, less healthy plant foods,
and animal foods. And healthy plant foods were
protectively associated, animal foods were
detrimentally associated, and less healthy plant foods were more
neutral when it came to diabetes risk. Here’s what the graph looks like:
higher diabetes risk with more and more animal foods, no protection
whatsoever with junky plant foods, and lower and lower diabetes risk
associated with more and more healthy whole plant foods in the diet. So, they conclude that yes, plant-
based diets are associated with substantially lower risk of
developing type 2 diabetes, but it may not be enough to just
lower the intake of animal foods, but also less healthy plant foods as well.
Video Transcript – As found on YouTube
The Healthiest Natural Source of Iodine
"The Healthiest Natural Source of Iodine" Dairy milk supplies between a quarter and
a half of the daily iodine requirement in the United States, though milk
itself has little native iodine. The milk iodine content is mainly
determined by factors like the application of iodine-
containing teat disinfectants. The iodine residues in milk
appear to originate mainly from the contamination
of the teat surface. The teats are sprayed or dipped with
like betadine-type disinfectants, and the iodine just kind
of leaches into the milk.
Too bad most of the plant-
based milks on the market aren't enriched
with iodine, too. Fortified soy milk is probably
the healthiest of the plant milks, but even if it was enriched with iodine,
what about the effects of soy on thyroid function? It's funny, when I searched the
medical literature on soy and thyroid, this study popped up: a cost-effective way to train
residents to do thyroid biopsies. Just stick the ultrasound probe
right on top and go to town. It turns out on ultrasound your
thyroid gland looks a lot like tofu. Anyway, the idea that soy may
influence thyroid function originated over eight decades ago when
marked thyroid enlargement was seen in rats fed raw soybeans, though the
observation that people living in Asian countries have consumed
soy foods for centuries with no perceptible thyrotoxic effects
certainly suggests their safety.
The bottom line is there does
not seem to be a problem with people who have
normal thyroid function. However, soy foods may inhibit
the oral absorption of Synthroid, thyroid hormone replacement
drugs, but so do all foods. That's why we tell patients to take it
on an empty stomach. But you also have to be getting enough iodine,
so it may be particularly important for soy food consumers to make sure
their intake of iodine is adequate.
What's the best way to get iodine?
For those who use table salt, make sure it's iodized. Currently, only half of table
salt sold contains iodine, and the salt used in processed
foods is typically not iodized. Of course, ideally, we
shouldn't add salt at all. Dietary salt is a public health hazard.
Think this title is a little over the top? Dietary salt is the #1 dietary risk
factor for death on the planet Earth, wiping out more than
three million people a year twice as bad as not
eating your vegetables. What's the best source of iodine, then? Sea vegetables! You can get
a little iodine here and there from a whole variety of foods, but the most concentrated source
by far, with up to nearly 2,000% of your daily allowance
in just a single gram— which is like the weight
of a paperclip: seaweed.
Given that iodine is extensively stored
in the thyroid, it can be safely consumed intermittently, meaning you
don't have to get it every day, which makes seaweed use
in a range of foods attractive, and occasional seaweed intake
enough to ensure iodine sufficiency. However, some seaweed
should be used with caution due to its overly high iodine
content, like kelp. Too much iodine can
cause hyperthyroidism, a hyperactive thyroid gland.
A woman presented with a racing heartbeat, insomnia,
anxiety, and weight loss thanks to taking just two
tablets a day containing kelp. In my last video, I noted how the
average urinary iodine level of vegans was less than the ideal levels, but
there was one kelp-eating vegan with a urinary concentration over 9,000.
Adequate intake is when
you're peeing out 100 to 199. Excessive iodine intake is when you
break 300; 9,437: way too much. The recommended average daily intake
is 150 mcg/day for non-pregnant, non-breastfeeding adults, and we may want
to stay below 600 on a day-to-day basis, whereas a tablespoon of
kelp may contain 2,000. I'd stay away from kelp
because it has too much, and stay away from hijiki because
it contains too much arsenic. Here's how much common seaweed
preparations should give you an approximate daily allowance:
two nori sheets, you can literally just nibble on them
as snacks like I do; one teaspoon of dulse flakes, which
you can just sprinkle on anything; one teaspoon of dried arame, which
is great for like adding to soups; or one tablespoon of seaweed salad. If iodine is concentrated in marine
foods, this raises the question of how early hominins living in
continental areas could have met their iodine requirements. Well, here's what bonobos do,
perhaps our closest relatives.
During swamp visits, they
all forage aquatic herbs..
Video Transcript – As found on YouTube
The Best Diet for Cancer Patients
"The Best Diet for Cancer Patients" Our lifetime risk of
developing an invasive cancer, not like some superficial skin
cancer or like ductal carcinoma of the breast, but serious
cancer is about 40%. Two in five of us are going to get a
cancer diagnosis in our lifetimes. What can we do to reduce our risk? Only about 5% of cancers are caused by problem genes we
inherited from our parents. The other 95% are
caused by mutations in our DNA we acquire
in our lifetimes. For example, based on a genetic
analysis of lung cancer, smokers may acquire an
average of one DNA mutation for every 15 cigarettes smoked.
Smoking is bad, but the number one
cause of these mutations is our diet, and that’s not even including
the cancers attributed to obesity. I’ve got tons of videos on dietary
approaches to prevent cancer, but what if you
already have it? Well-meaning professionals
sometimes counsel cancer patients to “Eat whatever you want.“ Given the time constraints that doctors
face, it may be understandable that the treating oncologist,
the treating cancer doctor, may be reluctant to engage in
a conversation about nutrition, but given the critical
role that diet may play, perhaps it should be a critical
part of their job to be able to answer patients’ questions
about nutrition before and after cancer treatment
and not default to the unhelpful “it doesn’t really matter,
eat whatever you want” which may not be in the
best interest of the patient.
The official recommendation of the American Institute
for Cancer Research, a leading authority
on diet and cancer, is that those with cancer
should follow the same diet that helps prevent cancer from
taking root in the first place. That means more whole grains,
vegetables, fruits, and beans, while limiting fast food, processed
food, meat, soda and alcohol. Similar recommendations have been put forth by other cancer authorities: more fruit, vegetables,
whole grains, and beans, and less salt, sugar,
meat, and alcohol. Cancer survivors adhering to
these guidelines do seem to live significantly longer, or at
least older female cancer survivors, the only group in which
it’s been looked at so far. They add that there are certain
foods that may be beneficial in cancer care including: beans,
berries, cruciferous vegetables, flaxseed, garlic, green tea,
tomatoes, and others, but emphasizes it’s not about a single
magic bullet food or component, but the combination of foods in
a predominantly plant-based diet. Here’s how some popular diets
used by cancer patients stack up. The so-called alkaline diet
gets high marks for being vegetable-focused and encouraging
people to cut down on animal foods.
The keto diet does the worst,
though they get points for keeping people away from refined grains,
alcohol and soft drinks. Macrobiotic diets win the day,
being closest to a whole food, plant-based diet, centered
around whole grains, vegetables, and beans though may not
be advising enough fruit. Paleo diets are a mixed bag with
insufficient whole grains and beans and too much meat, and the
vegan diet starts out strong, but doesn’t necessarily preclude
all manner of vegan junk food. Have any of these diets
been put to the test? I’ve done a video on the
abject failure of the keto diet.
The alkaline diet was tried
on eleven lung cancer patients. They lived an average of
28 and a half months, which is about 40% longer
than most patients have historically lived, but there
was no direct control group. The only diet proven in a
randomized controlled trial to reverse the progression of cancer
was Dr. Dean Ornish’s whole food plant-based lifestyle program,
which I’ve covered before. Most randomized controlled trials
to date on diet and cancer are like this, feasibility
studies just to see if we can get cancer patients to
eat healthier.
Period. Otherwise what’s the point
of even running the study? Here they did find they could get
patients with head and neck cancer to ramp up green leafy and
cruciferous vegetable intake up to 9 cups a week, so it’s at
least something you could test, but we don't yet have outcomes
data, but why wait? What’s the downside of
trying to eat healthier? It may even save your
life, another way. Cardiovascular disease competes with
breast cancer as the leading cause of death for older women
diagnosed with breast cancer. Researchers followed more
than 60,000 women diagnosed with breast cancer
over the age of 65 for an average of nine years,
by which time half had died. And the number one cause of death
was actually cardiovascular disease, edging out the breast cancer,
and so choosing a healthy diet centered around whole plant foods,
the only diet ever proven to reverse heart disease
in the majority of patients, may save your life, whether
you have cancer or not.
Video Transcript – As found on YouTube
Update on Vegetarian Stroke Risk
"Update on Vegetarian Stroke Risk" Healthy plant-based diets
have been associated with lower all-cause mortality,
up to a 34 percent lower risk of death from any cause over an average
of an eight-year period, just being in the top
versus bottom quarter of healthy plant-based consumption. If sustained, that could translate
into more than four extra years of life. A meta-analysis of a dozen studies
prospectively following more than a half a million people
for up to 25 years similarly found significantly lower
heart disease and overall death rates among those eating more plant-based.
No surprise,
a systematic review concluded since plant-based diets
may arrest or even reverse our number one killer—
cardiovascular disease. Those eating wholly plant-based
tend to be significantly slimmer with lower LDL cholesterol, triglycerides,
blood sugars, blood pressures, significantly less inflammation,
and less carotid artery wall thickening (a sign of atherosclerosis measured
via ultrasound in the neck), as good as what you see
in endurance athletes who’ve run an average of 50,000 miles,
which is like twice around the globe. And changes in risk factors
can happen fast, as evidenced by results
from one to three-week ad libitum (eat-all-you-want)
plant-based “kickstart” programs. For example, the results from the first
few hundred participants of the at-home
15-day Jumpstart program created by the nonprofit Rochester
Lifestyle Medicine Institute were recently published.
On a whole food plant-based diet,
obese patients lost an average of 7 pounds without controlling portions
or counting calories or carbs. Diabetics saw their fasting blood sugars
drop 28 points. Those with LDL cholesterol
over 100 experienced a 33-point drop (comparable to some statin drugs), and hypertensive individuals
experienced a 17-point drop in systolic blood pressure,
which is better than drugs, and all within just two weeks! Studies dating back nearly 40 years
show those eating meat-free diets also have improved blood “rheology,”
meaning fluidity or flowability, which may play a role
in cardiovascular protection.
Subsequent interventional studies putting
the cross-sectional findings to the test, show that switching people
to a plant-based diet can improve rheology measurements
within three to six weeks. But might the blood of vegetarians flow
a bit too well, though? In 2019, a study of thousands
of British vegetarians called EPIC-Oxford found that they were at higher risk
of hemorrhagic (bleeding) stroke. They had such a lower risk
of heart disease that they still had less
cardiovascular disease overall (and a half dozen studies show no overall
increased risk of stroke mortality), but why the greater stroke incidence? I suggested it might be vitamin B12
deficiency, which can lead to excessive levels
of a stroke- associated metabolite called homocysteine
which is normally detoxified by B12. This is thought to be the reason
why vitamin B12 supplementation can improve artery function
of vegetarians. Vitamin B12 supplements
or fortified foods are critical for anyone eating plant-based,
but my 12-part video series on vegetarians and stroke risk
triggered by the 2019 publication was all in vain.
It turns out vegetarians don’t appear
to have higher stroke risk after all. In response to the EPIC-Oxford results,
researchers around the world scrambled to see if the findings
were merely a fluke. In 2020, UK Biobank, a massive study
following more than 400,000 volunteers, confirmed that vegetarians
had lower cardiovascular disease rates and importantly,
no increased incidence of stroke. And two studies from Taiwan
found vegetarians had significantly
lower risk of stroke. Following tens of thousands
of vegetarians for up to ten years, they only had about half the stroke risk
compared to nonvegetarians (including a 64 percent lower risk
specifically of hemorrhagic stroke). By 2021, Harvard researchers
had finished and published their analyses of the 200,000+ participants
of the Nurses’ Health Study, the Nurses’ Health Study II, and the Health Professionals
Follow-Up Study. They too found no increased stroke risk
for vegetarians and indeed a decreased risk of stroke among those eating
healthy plant-based diets.
A meta-analysis putting all the studies
together found that indeed the EPIC-Oxford data appeared
to be a fluke after all, finding, if anything, a lower risk
of stroke in a subgroup analysis. A 2022 systematic review
concluded that vegetarian and low-animal product diets are associated with a significantly
lower risk of bleeding strokes, a significantly lower risk
of clotting strokes, and a significantly lower risk
of total strokes across the board..
Video Transcript – As found on YouTube
