Posted on - 14 Comments on Does Smoking Increase Heart Disease? If So, Why?

Does Smoking Increase Heart Disease? If So, Why?

Mr. Heisenbug says that smoking is the best predictor of heart disease. (Not quite. A high Agatston score is a better predictor. For example.) It is the best lifestyle predictor. People who smoke, according to this, have a six-fold increased risk of heart disease compared to non-smokers.

Why would this be? Heisenbug points to a study that found that when smokers quit, the microbial diversity of their gut increased. He speculates that (a) smoking decreases microbial diversity, which is quite plausible and (b) decreased microbial diversity increases heart disease — which has some plausibility.

I commented:

It would be interesting to find other factors that have a big effect on microbial diversity and whether they are also associated with heart disease. The idea that smoking causes heart disease via its microbial effects predicts, or at least suggests, that a change that reduces microbial diversity a lot will increase heart disease.

Heisenbug replied:

The only lifestyle factor that we can safely say leads to a lack of microbial diversity is a diet that is low in fermentable fiber. And fiber intake is consistently linked (negatively) with heart disease. I’ve never seen data linking lower overall diversity to a decrease in risk for any disease. And lots showing the opposite.

I replied:

The stuff about diversity (fiber intake increases diversity and is associated with less heart disease, many associations of more diversity with less risk of Disease X, no associations in the opposite direction) is substantial support for your idea, in my opinion.

His theory, in other words, made a prediction that turned out to be correct. A large fraction of what we’re told about health hasn’t led to any correct predictions. Here is an idea about how to prevent heart disease, a major killer, that there is actually reason to believe. And Heisenbug can say whatever he wants, in contrast to a heart disease expert quoted, say, in the New York Times, who is under pressure to say certain things. So we can take what he says at face value.

Heisenbug replied:

I agree. Especially because there’s never been a good explanation WHY fiber has that effect on [he means “association with” — Seth] heart disease.

Suddenly I am a lot more interested in microbial diversity and the association of fiber and heart disease. Smoking has countless health effects — it increases many cancers, for example. Obviously it increases lung and throat cancer. This means there are many ways it could cause heart disease. Fiber is quite different than smoking and as far as I know has no effect on lung and throat cancer. If it could be established that fiber causes a reduction in heart disease (not just is associated with a reduction), that would be considerable evidence (but far from proof, of course) that microbial diversity influences heart disease.

Posted on - 4 Comments on Is Diabetes Due to Bad Sleep?

Is Diabetes Due to Bad Sleep?

When I started eating honey at bedtime to improve my sleep, my fasting blood sugar values suddenly improved. Alternate-day fasting had pushed them into the mid-80s; now they were often in the high 70s, values I had never seen before. Without long walks and alternate-day fasting, my fasting blood sugar values would have been more than 100, which is pre-diabetic.

This made me wonder: Does bad sleep cause diabetes? Plenty of evidence, I found, supports this idea. Here is one example:

Just three consecutive nights of inadequate sleep can elevate a person’s risk [of diabetes] to a degree roughly equivalent to gaining 20 to 30 pounds, according to a 2007 study at the University of Chicago. . . .This revelation backs up previous research from Yale and the New England Research Institutes, which showed that people who clock six hours or less of sleep a night are twice as likely to develop diabetes in their lifetime as those who snooze seven hours.

Here is another:

In the study, published in the October issue of the Journal SLEEP, short sleepers reported a higher prevalence of coronary heart disease, stroke and diabetes, in addition to obesity and frequent mental distress, compared with optimal sleepers who reported sleeping seven to nine hours on average in a 24-hour period. The same was true for long sleepers, and the associations with coronary heart disease, stroke and diabetes were even more pronounced with more sleep.

Maybe there is something to it.

 

 

 

Posted on - 5 Comments on Assorted Links

Assorted Links

  • The promise of Bitcoin (the platform). “Bitcoin encapsulates four fundamental technologies . . . “
  • Bacteria and our behavior
  • Alternate-day fasting by normal-weight subjects.  “These findings suggest that ADF is effective for weight loss and cardio-protection in normal weight and overweight adults.” The experiment lasted 12 weeks.
  • Small interesting psychology experiments. “Whenever I go to a conference, I hate to wear those silly stickers that say “HELLO!  MY NAME IS.” I just write “SATAN” in the blank space.”
  • Pomona College dean of students sneers at a more reality-based college. She said: “Discovery, empathy, adaptability is goal of broad-based education, prepares students for life, learning & jobs known & unknown.” As the author, John Tierney, says, “What makes some people at liberal-arts colleges so dismissive of, and condescending toward, institutions that actually train people for careers?” I encountered a similar attitude at Berkeley. At a faculty meeting, I praised someone’s research. Another professor complained that the research was “applied”.

Thanks to Donna Warnock.

Posted on - 21 Comments on Meat as Health Food, Food Preference as Wisdom

Meat as Health Food, Food Preference as Wisdom

A Chinese friend of mine had a cold. After a few weeks, she was still sick.  I suggested she eat meat — it would provide the amino acids needed to make antibodies. She did want to eat meat, she said, but her mom thought that meat was bad for a sick person — an idea from Traditional Chinese Medicine, I guess.

Yesterday I had a desire to eat meat. That was odd; I didn’t usually feel that way. I ate all the meat in the refrigerator (slices of cured meat) but it wasn’t much. I ate three eggs. That, too, was odd — usually one egg is plenty. In the evening, I distinctly wanted more meat but decided against going out to get some. This morning I woke up with the flu. I could tell by the joint pain. So that’s what joint pain is, I thought. I’d read about flu and written about it, but, before this morning, cannot remember having it.  How is the flu different from a cold? I once tried to find out. I might not have come down with today’s case of the flu were it not for two events: yesterday’s decision not to eat meat; and, the day before, running into a friend who had just left the house after being home-bound for four days with the flu. He shook my hand twice.

Humans (including me) are exceedingly gullible; my evolutionary explanation is that this makes us easier to lead. Gullibility — we believe something just because an authority says it — is cement. It keeps members of a group together. Better that 10 people do one thing (e.g., live in one place) than ten things, in many cases. Pointless to waste time on unresolvable and divisive arguments. Doctors, both Western and Eastern, take advantage of our gullibility. As my friend says, “doctors hurt you” because they tell you to do something different from what you want to do (e.g., eat meat). What you want to do is actual wisdom. We’ve been shaped by evolution to want to do what is good for us and what we want to eat is a giant clue to what we should eat. In nutrition research, this line of thinking, which is called dietary self-selection research, is nearly moribund, in spite of we need to eat fermented foods to be healthy. Fermented foods, much more than other foods, satisfy our desire for sour, umami-flavored and complex-flavored foods. For example, it is easy to produce complexity via fermentation; it is hard to produce it in other ways.

As for my flu, I went to the store and got pork and duck. By evening I felt much better.

 

Posted on - 8 Comments on Does Intermittent Fasting Improve Repair Processes?

Does Intermittent Fasting Improve Repair Processes?

After I blogged about benefits of alternate-day fasting, a software engineer named Brandon Berg commented:

I had had plantar warts for a couple of years prior to starting IF (eating in a four-hour window each night). They cleared up almost immediately.

I had never heard about this effect of fasting. And the Wikipedia entry on plantar warts said nothing about this. I asked Brandon for details. Continue reading “Does Intermittent Fasting Improve Repair Processes?”

Posted on - 19 Comments on Dangerous Noise and “Doctors Hurt You”

Dangerous Noise and “Doctors Hurt You”

I have a friend with life-altering hyperacusis, a hearing problem where ordinary sounds can cause pain. It started after she worked in a noisy workplace for three years.

“People are always told about things they should do for good health: eat right, exercise, wear sunscreen, don’t smoke,” said my friend. “But they are almost never warned about loud noise, and if they are, it’s only about hearing loss far off in the future.” Her healthcare philosophy is doctors hurt you, which she finds so self-evident that she can barely explain why she believes it.

Her husband has hyperacusis, too, even worse than hers. His came from too many rock concerts. He sought medical treatment for a disorder that even Google has barely heard of, and now takes a staggering amount of pain medicine. His philosophy, at least historically, has been doctors help you. She has done her best to keep him away from doctors, but there is no doubt that, through a combination of bad advice and bad treatment, doctors have made his health much worse. (The pain medicines do reduce pain — but much of his pain was caused by doctors.) Judging by his and her experience, doctors hurt you is more accurate.

I am writing this in the loudest Starbucks I have ever been in, in New York City. (I have been in hundreds of Starbucks.) Three employees have told me they cannot control the volume of the music. Even with my Bose noise-cancelling headphones, it is too loud. I must find somewhere else. A friend who used to work at Starbucks disputes their claim that they cannot control the volume. She says the content of the music is set by corporate but the volume is controllable at individual stores. A customer at the loud Starbucks told me he thought the employees made the music so loud to drive customers away.

Exhibit 1 in the argument that doctors hurt you is tonsillectomies, probably the most common operation ever. Your tonsils are part of your immune system — removing them makes as much sense as removing part of your brain. Tonsillectomies remained common long after it was clear that tonsils were part of the immune system. Perhaps doctors didn’t understand high school biology? Or they didn’t care? Either answer suggests that doctors should be avoided.

 

 

Posted on - 6 Comments on Magnesium and Rectum Healing

Magnesium and Rectum Healing

After I posted a link to an article about magnesium deficiency (“50 studies suggest that magnesium deficiency is killing us”), a reader who wishes to be anonymous looked into it.

After reading your post about magnesium oil, I read up on it, and thought I’d try it. I didn’t notice any difference, but I have a report. In my reading, I came across stories of people who sprayed the oil on wounds.

I have a recurring minor irritation that, when it occurs, usually takes weeks to heal. Passing a large stool can cause small tears in the rectum, so small they don’t even bleed but nonetheless can be felt.  If another stool, even a regular-sized one, passes before the tears heal, they are painfully re-opened, though not re-opened fully. The pain is not severe but is, frankly, a pain in the ***.   In my case it usually takes weeks for the tears to completely heal.

I was a couple weeks into this cycle when my bottle of magnesium oil arrived.  I had read that it promotes healing and some people spray it on wounds.  So I sprayed it on my irritated area once a day for three days, and on the third day when I passed a stool there was no pain!   Never before had it healed so quickly, and I’ve had this problem at least once a year for over ten years.

I’m impressed. This resembles a theory making an unlikely prediction that turns out to be true. Other examples of magnesium benefits are here and here. Maybe magnesium will improve my sleep. That should be easy to test.

Posted on - 4 Comments on Organic Pollutants Associated With Diabetes

Organic Pollutants Associated With Diabetes

Everyone knows that diabetes is associated with obesity, probably because obesity causes diabetes. However, thin people also become diabetic. A clue to why is provided by the correlation between diabetes and what are called “persistent organic pollutants” (POPs). POPs are man-made organic compounds, usually pesticides, such as polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans.

A 2006 study using NHANES (National Health and Nutrition Examination Survey 1999–2002) data found very strong associations between levels of these chemicals and diabetes. For example, a risk ratio of 30. These associations persisted even when the data was stratified in all sorts of ways. The scariest result came from people who had BMI < 25. Looking only at such people, those above the 90th percentile for amount of POPs had 16 times the risk of diabetes as those below the 25th percentile. Here is something associated with thin people getting diabetes.

Does the association exist because POPs cause diabetes? You might argue that POP exposure is correlated with poverty (poor people are more exposed), poor people exercise less than rich people, and lack of exercise causes diabetes. However, Agent Orange exposure among soldiers is associated with diabetes. That is unlikely to be due to confounding with poverty or lack of exercise.

Everyone has these chemicals in their body, but almost no one knows how much. I don’t know if I’m in the 10th percentile or the 90th percentile. If I’m in the 90th percentile, what can I do about it? A good place for self-measurement and tracking.

Posted on - 3 Comments on First Effects of Intermittent Fasting

First Effects of Intermittent Fasting

Jeff Winkler described his first weeks of intermittent fasting:

Annual physical July 2nd [2013], HDL 46, cholesterol 243, LDL 177. Doc pushing for statins. I’ve been taking 5000 IU D3, some zinc, eating vaguely low carb. Had a kid a couple years ago. Watched Eat Fast, Live Longer. Was blown away.

Decided to try intermittent fasting and use $500 USB ultrasound device (BodyMetrix) for feedback. Conclusions after three weeks:

  • It’s not hard. I’m eating within an 8-hour window. Usually try to eat first food at 9 AM, close the window 8 hours after. I’m hardly ever hungry. Now it’s like “oh, it’s 9, guess I should eat”. I’m not eating specially or restricting my intake.
  • Losing weight. About 237->231 in 20 days.

For me, the novelty was his BodyMetrix data (mm of subcutaneous fat). Here it is:
winkler

This shows fat loss from the thigh and waist; the chest measurements vary too much to see a trend. The BodyMetrix data and the weight data (237–>231) confirm each other. He also used an Omron measurement device that uses impedence to measure body fat. You hold it in your hands. Its data were too noisy to conclude anything.

All in all, Winkler’s scale did a good job of detecting weight loss, the BodyMetrix device added a bit (confirmed the weight loss was due at least partly to fat loss), and the Omron device added nothing. The BodyMetrix device is advertised with the claim “no embarrassing pinching” but I’m sure pinching (with calipers) to measure skinfold thickness would have been more accurate.

Posted on - 9 Comments on “Hunger is a Necessary Nutrient” (Ancestral Health Symposium 2013)

“Hunger is a Necessary Nutrient” (Ancestral Health Symposium 2013)

Nassim Taleb said this or something close to it on the first day of the Ancestral Health Symposium in Atlanta, which was yesterday. Danielle Fong told me something similar last week: We should use all of our metabolic pathways. Of course it is hard to know what metabolic pathways you are using. In contrast, Taleb’s point — not original with him, but a new way (at least to me) of summarizing research — is easily applied.

What I know overwhelmingly supports Taleb’s point. 1. When I did the Shangri-La Diet the first time, I was stunned how little hunger I felt. This wasn’t bad — presumably my set point had been too high, lack of hunger reflected the dropping set point, it was good to know how to lower the set point — but it was dreary, not feeling hunger. It was as if life had gone from color to black and white. Something was missing. 2. Data supporting the health benefits of intermittent fasting, which produces more hunger than the control condition. 3. The experience of my friend who had great benefits from alternate-day fasting. He told me he had never felt hunger before, at least of that magnitude. A great increase in hunger, in other words, happened at exactly the same time as a great improvement in health.

Obviously Taleb is talking about hunger caused by lack of food, rather than hunger caused by learned association (if you eat at noon every day you will become hungry at noon, if you eat every time you enter Store X, you will be come hungry when you enter Store X, the existence of this effect is why they are called appetizers). The Shangri-La Diet reduces your set point but only if your set point controls when/how much you eat is this going to make a difference. So to lose weight you need to do two things: 1. Lower your set point. 2. Lower your weight to your set point. While SLD certainly does #1, it does not do #2. You can make sure your weight is near your set point if you feel strong hunger if you don’t eat for a while.

Taleb’s comment suggests focussing on the outcome of fasting, rather than on its duration or frequency. Instead of fasting every other day (or whatever), fast until you feel strong hunger. How often you need to do this, how strong the hunger should be, are questions to answer via trial and error.

 

 

Posted on - 9 Comments on Alternate Day Fasting: Not For Everyone?

Alternate Day Fasting: Not For Everyone?

I’ve been doing alternate day fasting for about two months. I find it very easy. In several ways it’s easier than eating every day:

  • save time
  • save money
  • less constrained on eating days
  • a little more hungry than usual on fasting days (up to a point hunger is pleasant — when the Shangri-La Diet wiped out all my hunger, I didn’t like it)
  • sense of accomplishment when I wake up after a fasting day (I did it)
  • food tastes better

Maybe my friends are unusually tolerant but I have yet to encounter a serious negative. Yesterday, a fasting day, I happily watched a friend eat dinner. I had two bites out of curiosity. I saw nothing to suggest it made her uncomfortable I wasn’t eating.

However, a different friend has told me that alternate day fasting made her sick. She did it for about three months, felt worse and worse, and finally stopped. She believes it works less well for women than for men. I suspect a heavy exercise routine (she ran a lot) made alternate day fasting more difficult. But there is also the best-selling book The FastDiet. It has two authors, a man (Michael Mosely, a doctor) and a woman (Mimi Spencer, a journalist). The book contains a remarkably short and remarkably unenthusiastic description of Spencer’s experience with intermittent fasting. Maybe it didn’t agree with her, either.

Posted on - 11 Comments on More About Benefits of Alternate Day Fasting

More About Benefits of Alternate Day Fasting

Last week I blogged about a friend who derived great benefits from alternate-day fasting. There were several reader questions. I put them to my friend:

Q How does exercise fit in with all this fasting?

A I do Iyengar yoga every day, about 2 hours.

Q I assume he drank water. Did he consume any liquid calories or probiotics (Yakult?) on his fasting days?

A Yes, water. I replace electrolytes, but that’s for other reasons.  (I don’t regulate electrolytes well.)  There may have been 8 or 10 days in the last 9 months when I had a very small amount of food on a fasting day — a little yogurt or a little rice & sauerkraut, maybe.

Q What did he eat on non-fasting days?

A Breakfast of stir-fry + egg + some fruit & yoghurt & nuts & flax seeds. Maybe I break that into two meals or maybe not. Dinner of … veggies/rice/chicken or … something like that. [He didn’t change what he ate when he started alternate-day fasting.]

Q Something is missing in the story. He didn’t get to be an Ivy League math professor by being confused, exhausted, overwhelmed and depressed all the time. Were his indigestion and tiredness increasing in severity before he started the diet?

A I was severely ADHD all my life, and collapsed in the early 2000’s. I turned out to suffer from heavy metal poisoning: mercury, lead and a little bit of arsenic. I’ve been detoxing for a number of years with steady improvement. As to how I managed to become an Ivy League math professor, that’s not unusual. There are a lot of us. There is a subtype of ADHD called “with hyperfocus”. Hyperfocus is a mild form of the Asperger’s “little professor” syndrome, in which a person is completely consumed by one subject, at the expense of anything else.

Posted on - 17 Comments on Benefits of Alternate Day Fasting

Benefits of Alternate Day Fasting

A friend of mine named Dave saw the BBC program Eat, Fast and Live Longer ten months ago. The program promotes intermittent fasting for better health. It sounded good. Already he often went a day without food. Some Brahmins in South India had eaten this way for millennia – which suggested it made some sense. It wasn’t a fad. Alternate day fasting was simpler than the “fast 2 days per week” regimen the TV show ended with. He started alternate day fasting immediately. Continue reading “Benefits of Alternate Day Fasting”

Posted on - 5 Comments on Assorted Links

Assorted Links

  • self-tracking neuroscientist. I have only learned from tracking when I am adventurous — when I change stuff, such as what I eat. I will be curious to see if the same thing happens here. The initial thought when tracking yourself is “keep things constant” so that the data from different days will be more comparable. This makes sense if you are doing an experiment where different days get different treatments. It does not make sense when you are not doing an experiment. This self-tracker doesn’t seem to be doing any experiments, so he should allow his life to be messy if he wants to learn more.
  • Interview with Renata Adler
  • Alternate-day fasting thread at Mark’s Daily Apple
  • An essay on the effect of immigrants on “economic freedom” (via Marginal Revolution) does not mention the fact that immigrants bring new ideas and skills. This is an example of the way economists usually ignore innovation, which benefits from new ideas and skills. Innovations usually derive from new combinations of things. To open a new business (an instance of economic freedom) it really helps to have a new good or service. New cuisines (immigrants open restaurants) is just the beginning.

Thanks to Dave Lull.

Posted on - 4 Comments on David Grimes Responds to Comments

David Grimes Responds to Comments

In recent posts (here, here, and here), I’ve described the ideas of David Grimes, a British doctor, about the cause of heart disease. Grimes recently responded to comments on the last post:

First, to develop the latitude theme, that distance from the equator determines risk of heart disease, cancers, multiple sclerosis and others. Four visual pieces of evidence for you.

Sunshine_Average_1971-2000_1 (1)

The sunshine map of the UK: We see what would also be the map of multiple sclerosis and CHD in the UK — both diseases most common in the west of scotland and least common in the south-east of England. Similar pattern of average life expectancy.

Look at cancer incidence in North America for another latitude effect.

Then there is breast and colon cancer in Europe:

But the [most] important observation of the sun being protective against cardiovascular disease comes from the USA. A latitude effect is present but weak. However a longitude effect is powerful. It works out as an altitude effect — the higher the altitude of residence the lower the risk of death from cardio-vascular disease (coronary heart disease + stroke). It is interesting to note the mirror image of the land profile from east to west and the CVD death profile. This can be explained most simply and most plausibly by the higher UV exposure at higher altitudes.

This is a powerful supplement to the latitude observations in Europe. The [north-south] length of Europe is worth remembering: the north of Scotland is the same latitude as Hudson Bay. In the north of England I live further north than anywhere in China. This means big sun exposure effects.

The size of the disease differences is impressive — e.g., a factor of 2. I think these sunshine correlations are due either to a protective effect of Vitamin D or a protective effect of sleep (more sunshine = better sleep). There’s no doubt that sleep quality depends on the amplitude of a circadian rhythm (greater amplitude = better sleep), which in turn depends on the amplitude of the sunlight intensity rhythm, the day-night difference.

Posted on - 4 Comments on Does Alternate-Day Fasting Lower HbA1c?

Does Alternate-Day Fasting Lower HbA1c?

2013-07-01 HbA1c versus date (after starting alternate day fasting)

This graph shows my HbA1c values in recent years. After a lot of variation, they settled down to 5.8, which was the measurement a month ago. 5.8 isn’t terrible — below 6.0 is sometimes called “okay”) — but there is room for improvement. In a large 2010 study, average HbA1c was 5.5. The study suggested that a HbA1c of about 5.0 was ideal.

Three weeks ago I started alternate-day fasting (= eating much less than usual every other day) for entirely different reasons.  Continue reading “Does Alternate-Day Fasting Lower HbA1c?”

Posted on - 13 Comments on Alternate-Day Fasting Improved My Fasting Blood Sugar

Alternate-Day Fasting Improved My Fasting Blood Sugar

A few days ago, I gave a talk at a Quantified Self Meetup in San Francisco titled “Why is my blood sugar high?” (PowerPoint here and here). My main point was that alternate-day fasting (eating much less than usual every other day) quickly brought my fasting blood sugar level from the mid-90s to the low 80s, which is where I wanted it. I was unsure how to do this and had tried several things that hadn’t worked.

Not in the talk is an explanation of my results in terms of setpoint (blood sugar setpoint, not body fat setpoint). Your body tries to maintain a certain blood sugar level — that’s obvious. Not obvious at all is what controls the setpoint. This question is usually ignored — for example, in Wikipedia’s blood sugar regulation entry. Maybe Type 2 diabetes occurs because the blood sugar setpoint is too high. If we can find out what environmental events control the setpoint, we will be in a much better position to prevent and reverse Type 2 diabetes (as with obesity).

A few years ago, I discovered that walking an hour per day improved my fasting blood sugar. Does walking lower the setpoint? I didn’t ask this question, a curious omission from the author of The Shangri-La Diet. If walking lowered the setpoint, walking every other day might have the same effect as walking every day.

I was pushed toward this line of thought because alternate-day fasting seems to lower the blood-sugar setpoint. After I started alternate-day fasting, it took about three days for my fasting blood sugar to reach a new lower level. After that, it was low every day, not just after fast days. My experience suggests that the blood-sugar setpoint depends on what your blood sugar is. When your blood sugar is high, the setpoint becomes higher; when your blood sugar is low, the setpoint becomes lower. Tim Lundeen had told me something similar to this.

If you tried to lower your fasting blood sugar and succeeded, I hope you will say in the comments how you did this. I tried three things that didn’t work: darker bedroom, Vitamin B supplement, and cinnamon. Eating low carb raises fasting blood sugar, according to Paul Jaminet.

Posted on - 9 Comments on Heart Disease Epidemic and Latitude Effect: Reconciliation

Heart Disease Epidemic and Latitude Effect: Reconciliation

For the last half century, heart disease has been the most common cause of death in rich countries — more common than cancer, for example. I recently discussed the observation of David Grimes, a British gastroenterologist, that heart disease has followed an infectious-disease epidemic-like pattern: sharp rise, sharp fall. From 1920 to 1970, heart disease in England  increased by a factor of maybe 100; from a very low level to 500 deaths per 100,000 people per year. From 1970 to 2010, it has decreased by a factor of 10. This pattern cannot be explained by any popular idea about heart disease. For example, dietary or exercise or activity changes cannot explain it. They haven’t changed the right way (way up, way down) at the right time (peaking in 1970). In spite of this ignorance, I have never heard a health expert express doubt about what causes heart disease. This fits with what I learned when I studied myself. What I learned had little correlation with what experts said.

Before the epidemic paper, Grimes wrote a book about heart disease. It stressed the importance of latitude: heart disease is more common at more extreme latitudes. For example, it is more common in Scotland than the south of England. The same correlation can be seen in many data sets and with other diseases, including influenza, variant Creuztfeldt-Jacob disease, multiple sclerosis, Crohn’s disease and other digestive diseases. More extreme latitudes get less sun. Grimes took the importance of latitude to suggest the importance of Vitamin D. Better sleep with more sun is another possible explanation.

The amount of sunlight has changed very little over the last hundred years so it cannot explain the epidemic-like rise and fall of heart disease. I asked Grimes how he reconciled the two sets of findings. He replied:

It took twenty years for me to realize the importance of the sun. I always felt that diet was grossly exaggerated and that victim-blaming was politically and medically convenient – disease was due to the sufferers and it was really up to them to correct their delinquent life-styles. I was brought up and work in the north-west of England, close to Manchester. The population has the shortest life-expectancy in England, Scotland and Northern Ireland even worse. It must be a climate effect. And so on to sunlight. So many parallels from a variety of diseases.

When I wrote my book I was aware of the unexplained decline of CHD deaths and I suggested that the UK Clean Air Act of 1953 might have been the turning point, the effect being after 1970. Cleaning of the air did increase sun exposure but the decline of CHD deaths since 1970 has been so great that there must be more to it than clean air and more sun. At that time I was unaware of the rise of CHD deaths after 1924 and so I was unaware of the obvious epidemic. I now realize that CHD must have been due to an environmental factor, probably biological, and unidentified micro-organism. This is the cause, but the sun, through immune-enhancement, controls the distribution, geographical, social and ethnic. The same applies to many cancers, multiple sclerosis, Crohn’s disease (my main area of clinical activity), and several others. I think this reconciles the sun and a biological epidemic.

He has written three related ebooks: Vitamin D: Evolution and Action, Vitamin D: What It Can Do For Your Baby, and You Will Not Die of a Heart Attack.

Posted on - 7 Comments on Sunlight and Heart Disease

Sunlight and Heart Disease

Vitamin D and Cholesterol: The Importance of the Sun (2009) by David Grimes, a British doctor, contains more than a hundred graphs and tables. Most of the book is about heart disease.  Grimes argues that a great deal of heart disease is due to too little Vitamin D, usually due to too little sunlight. I recently blogged about other work by Dr. Grimes — about the rise and fall of heart disease.

Part of the book is about problems with the cholesterol hypothesis (high cholesterol causes heart disease).  One study found that in men aged 56-65, there was no relationship between death rate and cholesterol level over the next thirty years, during which almost all of them died (Figure 29.2). There is a positive correlation between death rate and cholesterol level for younger men (aged 31-39). The same pattern is seen with women, except that women 60 years or older show the “wrong” correlation: women in the lowest quartile of cholesterol level have by far the highest death rate (Figure 29.5). A female friend of mine in England, who is almost 60, was recently told by her doctor that her cholesterol is dangerously high.

The book was inspired by Grimes’ discovery of a correlation between latitude and heart disease: People who lived further north had more heart disease. This association is clear in the UK, for example (Figure 32.4). Controlling for latitude, he found a correlation between hours of sunshine and heart disease rate (Table 32.3): Towns with more sunshine had less heart disease. No doubt you’ve heard that dietary fat causes heart disease. In the famous Seven Countries study, there was indeed a strong correlation between percent calories from fat and heart disease death rate (Figure 30.2). You haven’t heard that in the same study there was a strong correlation between latitude and dietary fat intake (Figure 30.8): People in the north ate more fat than people in the south. The fat-heart disease correlation in that study could easily be due to a connection between latitude and heart disease. The correlation between latitude and heart disease, on the other hand, persists when diet is controlled for.

Grimes convinced me that the latitude/sunshine correlation with heart disease reflects something important. It is large, appears in many different contexts, and has resisted explanation via confounds. Maybe sunshine reduces heart disease by increasing Vitamin D, as Grimes argues, or maybe by improving sleep — the more sunshine you get, the deeper (= better) your sleep. Sleep is enormously important in fighting off infection, and a variety of data suggest that heart disease has a microbial aspect. As long-time readers of this blog know, I take Vitamin D3 at a fixed time (8 am) every morning, thereby improving my Vitamin D status and improving my sleep.

Grimes and his book illustrate my insider/outsider rule: To make progress, you need to be close enough to the subject (enough of an insider) to have a good understanding but far enough away (enough of an outsider) to be able to speak the truth. As a doctor, Grimes is close to the study of disease etiology. However, he’s a gastroenterologist, not a cardiologist or epidemiologist. This allows him to say whatever he wants about the cause of heart disease. He won’t be punished for heretical ideas.