Why Japanese Men Have Far Less Heart Disease
Coronary artery disease, the type that causes heart attacks and is generally known as heart disease, is the leading killer in the U.S., and men have much higher rates of it than women. Things are different elsewhere, such as in Japan; this article will tell you why Japanese men have far less heart disease than Americans.
Virtually every man is taught to fear heart disease, with good reason, and wants to do everything to prevent it.
Heart disease rates are much higher in the U.S. and the UK than many other places, such as Japan. Dr. Malcolm Kendrick posted the following stats, taken from the article “Cardiovascular Disease and Risk Factors in Asia”.1
In Japan, the percentage of men who smoke is 35.4%, more than double the rate of 17.2% in the U.S.
Their average systolic blood pressure is 130.5, compared to 123.3 in the U.S.
The cholesterol level averages 201 mg/dl (5.2 mmol/L) vs 197 mg/dl (5.1 mmol/L) in the U.S.
The rate of diabetes in Japan is 7.2%, vs 12.6% in the U.S.
Yet the rate of coronary heart disease among Japanese men is less than one third that of the U.S. at 45.8 (per 100,000/year), while American men have a rate of 150.7.
Dr. Kendrick wished to make a point about cholesterol, namely that it cannot be a risk factor.
The point I wish to make is: can we learn from the Japanese experience and keep our heart disease risk low?
Japanese men smoke cigarettes at twice the rate of American men, have higher cholesterol and higher blood pressure, yet they have about 30% the rate of heart disease as in the U.S.
Note that their rate of diabetes is about 60% that of the U.S.; that’s important.
Here are some candidates for the lower male Japanese heart disease rate, along with what I believe are the best answers.
Maybe the Japanese have some kind of genetic protection against heart disease.
Unfortunately for that thesis, Japanese men who move to the U.S. have much higher rates of heart disease than Japanese men in Japan.2
The incidence rate was lowest in Japan where it was half that observed in Hawaii. The youngest men in the sample in Japan were at particularly low risk. The incidence among Japanese men in California was nearly 50 percent greater than that of Japanese in Hawaii. A striking increase in the incidence of myocardial infarction appears to have occurred in the Japanese who migrated to the United States; this increase is more pronounced in California than in Hawaii.
No, Japanese genes do not offer protection.
The Japanese eat a lot more fish than Americans, and this is important, since omega-3 fatty acids, the type in which fish is abundant, are protective against heart disease.3
A study done in 2005 found that the more fish the Japanese ate, the higher was their consumption of omega-3 fats, and the lower was their rate of heart disease.4
The following chart shows the decline in heart disease risk with increasing omega-3 consumption.
At the highest quintile (fifth) of consumption, risk was ~70% less than the lowest quintile of consumption — and keep in mind that the risk in Japan is already low. The study also notes that the lowest quintile of fish consumption in Japan was equal to the third quintile in Western countries, meaning that for us Westerners, increasing our fish and/or omega-3 consumption could lower our heart disease risk greatly.
Sugar consumption is linked to heart disease, probably through its effects on insulin resistance. People who consume 2 or more sugar-sweetened drinks (SSBs) daily had a 35% greater risk of heart attack.5
In the U.S., the average person consumes 126 grams of sugar daily. That’s about 25 teaspoons.
The corresponding figure for Japan is 57 grams, or about 11 teaspoons. Less than half the amount as the U.S.
Trans fats are the artificial fats created in the making of vegetable oil and margarine. They are strongly implicated in coronary heart disease. Risk in highest quintile of consumption vs lowest is 50% higher.6
Processed food of all kinds, but especially baked goods, are loaded with trans fat. Margarine is basically about 100% trans fat and should never be used. Vegetable oils — throw them out. Use coconut oil, olive oil, lard, and butter instead.
Vitamin D deficiency is associated with heart disease, with a 62% higher rate in those who are deficient.7
Fish are high in vitamin D, and as we saw above, the Japanese eat a lot of fish.
Excessive iron is strongly associated with many diseases. As a rough and ready measure of iron status, we find that Japanese women are more than twice as likely to be anemic as American women.8
That tells us that both iron intake and iron levels are lower in Japan than in the U.S., and could be a big factor behind lower heart disease rates.
The U.S. obesity rate is 33%; in Japan, it’s 5%. As obesity is linked to heart disease, enough said.
Conclusion and steps to take
Men in Japan, despite smoking much more than American men, and despite higher cholesterol and blood pressure, have a rate of heart disease 70% lower than American men.
Among the reasons for this are high consumption of fish and omega-3 fats, more vitamin D, and less consumption of sugar, trans fats, and iron.
To lower your risk of heart attack:
- Eat fish and/or supplement with fish oil. In Japan, the category with the lowest risk ate fish 8 times a week, or an average of 180 grams (more than a third of a pound) daily. That meant a consumption of omega-3 fats of 2.1 grams daily, or the equivalent of about 2 teaspoons of cod liver oil. That’s a lot, but I take one teaspoon of cod liver oil several times a week, and I’m now going to increase that to every day.
- Avoid sugar in all forms. No sodas, fruit juice, candy, donuts — you get the idea. Small amounts, such as teaspoon in a cup of coffee, probably won’t do much harm.
- Avoid trans fats. That pretty much eliminates processed food, as well as margarine, mayonnaise, vegetable oils. Eat whole, unprocessed food.
- Get sunshine and/or supplement with vitamin D. I take 5,000 IU daily, less in summer when I get sun exposure. (That’s higher than mainstream medicine recommends, by the way.)
- Control your iron levels. Keep ferritin below 100.
- Stay lean. Don’t be overweight.
PS: Check out my book, Muscle Up.
- Ueshima, Hirotsugu, et al. “Cardiovascular disease and risk factors in Asia a selected review.” Circulation 118.25 (2008): 2702–2709.
- Robertson, Thomas L., et al. “Epidemiologic studies of coronary heart disease and stroke in Japanese men living in Japan, Hawaii and California: incidence of myocardial infarction and death from coronary heart disease.”The American journal of cardiology 39.2 (1977): 239–243.
- Harris, William S. “The omega-3 index as a risk factor for coronary heart disease.” The American journal of clinical nutrition 87.6 (2008): 1997S-2002S.
- Iso, Hiroyasu, et al. “Intake of fish and n3 fatty acids and risk of coronary heart disease among Japanese the Japan Public Health Center-Based (JPHC) Study Cohort I.” Circulation113.2 (2006): 195–202.
- Malik, Vasanti S., et al. “Sugar-sweetened beverages, obesity, type 2 diabetes mellitus, and cardiovascular disease risk.” Circulation 121.11 (2010): 1356–1364.
- Willett, Walter C., et al. “Intake of trans fatty acids and risk of coronary heart disease among women.” The Lancet 341.8845 (1993): 581–585.
- Wang, Thomas J., et al. “Vitamin D deficiency and risk of cardiovascular disease.” Circulation117.4 (2008): 503–511.
- Kusumi, Eiji, et al. “Prevalence of anemia among healthy women in 2 metropolitan areas of Japan.” International journal of hematology 84.3 (2006): 217–219.