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October 2010

DASH or fruit/veg diet and heart risk
Physical activity lowers heart risk
Magnesium reduces diabetes risk
Fish lowers prostate cancer mortality
Exercise helps fracture risk in elderly
Low testosterone increases mortality

DASH or fruit/veg diet and heart risk

The DASH diet (Dietary Approaches to Stop Hypertension) is rich in fruits and vegetables and whole grains, and contains nuts, fish, and low-fat dairy. It is also low in red meat, animal fat, sugar, and cholesterol. This is far healthier than the typical processed, meat-rich western diet, although it still has room for improvement.

Researchers evaluated 459 individuals with prehypertension or mild hypertension but not taking medication. They were assigned one of three diets: a control diet (typical American), the DASH diet, or a so-called “fruit/vegetable” (F/V) diet.

They followed the participants for eight weeks, and evaluated the risk of having a heart attack over the next 10 years using equations derived from the Framingham Heart Study. Those who were on the DASH diet were eating 11 servings of fruits and vegetables per day. Compared to those on the typical American diet, their risk of a heart attack was reduced by 18 percent. They also had lowered their LDL cholesterol by 7 percent and their systolic blood pressure by 7 points. Compared to those on the F/V diet, the DASH dieters had a reduction of heart attack risk of 11 percent. (Chen ST, et al., The effect of dietary patterns on estimated coronary heart disease risk: results from the Dietary Approaches to Stop Hypertension (DASH) Trial. Circ Cardiovasc Qual Outcomes. 2010 Sep 1;3(5):484-489.)

However, the “F/V” diet was not simply a diet of fruits and vegetables as you would suppose from the title. It was a typical American diet with added fruits and vegetables, so calling it a “fruit/vegetable” diet is misleading. These participants were still eating the meat, fat, and sugary foods that do the most damage, and the harm was mitigated a bit by adding fruits and vegetables. Eating a more vegetarian diet is even better than the DASH diet, as indicated by a large body of research with many participants and over longer time periods.

One expert was quoted in a news article (HealthDay, August 31, 2010) as saying that “changing risk factors does not always translate to a reduction in actual heart disease. It is therefore essential to hold dietary modification and other forms of lifestyle modification to the same gold standard [as] statins…” This is a disservice to people who might otherwise be encouraged to improve their diets. It is not necessary to hold diets to that same standard. Although we want good research on diets, the benefits of dietary improvement are clear and wide ranging. Statins, on the other hand, as well as antihypertensive medications, need a stronger standard because they have serious associated side effects and far greater expense. It is unwise to wait for “gold-standard” research before improving your diet – you might be dead by then!

Physical activity lowers heart risk

Physical activity can help prevent heart failure (HF), including leisure time exercise and work related activity, such as having a physical job or commuting by foot or bicycle. You don’t need a gym membership or a formal exercise routine to reap some benefits. However, combining work-related activity with leisure-time exercise provides even lower risk.

Researchers evaluated 28,334 Finnish men and 29, 874 women between 25 and 74 years old. During an average follow-up of over 18 years, 868 men and 1640 women developed HF. After adjusting for other contributors to HF, compared to those men whose exercise was rated as light, those who were most active were 35 percent less likely to have HF. For women high physical activity led to a 25 percent reduced risk. (Wang Y, et al., Occupational, commuting, and leisure-time physical activity in relation to heart failure among Finnish men and women. J Am Coll Cardiol. 2010 Sep 28;56(14):1140-8.)

For men, physical activity at work alone led to a 10 percent reduction in risk of HF, while for women the reduction was 20 percent. High levels of physical activity at work were defined as heavy manual labor with walking and lifting, such as industrial work or farm labor. Moderate leisure activity was defined as over four hours a week of walking, bicycling, or gardening. If you spend lots of time reading or at the computer (as I do) then a regular program of exercise (and/or heavy work in the garden) is almost essential to maintaining health.

Magnesium reduces diabetes risk

Magnesium is an essential mineral involved in hundreds of enzymatic reactions. It is important for muscles, especially heart muscle, and for metabolism of sugar and essential fatty acids. New research confirms further benefits from both high levels of intake from the diet and supplements and high levels in the blood. Western diets are commonly low in magnesium, while oriental diets are typically high, often containing twice as much.

Researchers followed 4497 Americans aged 18 to 30 years, who had no diabetes at the start of the study. They followed the subjects for 20 years. Compared to those in the lowest fifth of magnesium intake, those who consumed the most were only half as likely to develop diabetes. (Kim DJ, et al., Magnesium intake in relation to systemic inflammation, insulin resistance, and the incidence of diabetes. Diabetes Care. 2010 Aug 31. [Epub ahead of print])

In addition to the reduced diabetes risk, the researchers evaluated the subjects for inflammatory markers, such as high sensitivity CRP, interleukin-6, and fibrinogen (also a blood clotting factor) and for insulin resistance, all of which are associated with the development of diabetes and heart disease. High magnesium intake and high levels in the serum were consistently associated with lower levels of these inflammatory markers and less insulin resistance. This is perhaps one reason that whole grains are associated with a reduced diabetes risk, as they are rich in magnesium. Typical levels of magnesium that are beneficial are 400-800 mg per day.

Fish lowers prostate cancer mortality

Fish consumption appears to be helpful in prostate cancer. Around the world, prostate cancer incidence can vary up to 60-fold from country to country, suggesting a relationship to lifestyle and diet. Researchers did a meta-analysis (study of studies) to determine a relationship of prostate cancer to dietary fish. (Szymanski KM, et al., Fish consumption and prostate cancer risk: a review and meta-analysis. Am J Clin Nutr. 2010 Sep 15. [Epub ahead of print])

They evaluated 12 case-control studies (5777 cases and 9805 controls) and 12 cohort studies (totaling 445,820 subjects). While prostate cancer incidence was lower in those who consumed the most fish, this was not statistically significant. However, those who consumed the most fish had a 63 percent lower cancer-specific mortality. Because the studies were so varied in their methodology, they were not able to say how much fish one needs to eat to have the protective benefit.

It is not clear if the protection is due to the omega-3 oils in some fish, but in other studies this has been shown to slow cancer progression. Omega-3 oils are high in salmon, sardines, mackerel, and herring and a few other fish. I recommend wild fish (such as Alaskan salmon) as opposed to farmed fish for a number of reasons. In addition to better nutritional value, they are better for the environment. They are not kept in close proximity to each other and are not fed antibiotics and hormones to enhance their growth. (Also, it takes more protein from fish meal used to feed farmed fish than is produced in the end product.)

Exercise helps fracture risk in elderly

Exercise has benefits that go beyond the heart. It improves mobility and balance in the elderly, and new research suggests that it also helps to prevent fractures in women with low bone density (osteopenia). And the further good news is that it does not take extensive amounts of exercise to achieve the benefits.

In a randomized, controlled exercise trial, researchers followed 160 women with osteopenia, aged 70-73 years at the start of the study, for a total observation time of 7.1 years. They evaluated them for femoral neck bone mineral density, postural sway, and leg strength, as well as fractures requiring hospital treatment and functional ability. (Korpelainen R, et al., Long-term outcomes of exercise: follow-up of a randomized trial in older women with osteopenia. Arch Intern Med. 2010 Sep 27;170(17):1548-56.)

Compared with those who did not exercise, the women who exercised had a 32 percent lower incidence of fractures overall. The exercise group had no hip fractures compared to five fractures in the control group. Only 1 woman died in the exercise group compared to 8 deaths in the controls. Equally important, the exercisers had better walking speed and posture.

The subjects who had exercised all of their lives had a 78 percent overall reduction in the incidence of fractures during the follow-up time, even though the rate of decline in bone density in both groups was equal. Functional capacity was greater in the exercise group also.

Low testosterone increases mortality

New research shows low serum testosterone levels are associated with increased mortality from heart disease and other causes in spite of the prior misconception that testosterone was harmful to the heart . (Malkin CJ, et al., Low serum testosterone and increased mortality in men with coronary heart disease. Heart. 2010 Oct 19. [Epub ahead of print])

Researchers followed 930 men with heart disease for an average of 7 years. Those with low testosterone had 21 percent mortality, while those with normal levels had only 12 percent mortality. The excess risk was seen even with borderline low testosterone. Replacement with hormones could be beneficial to those with low levels. This can be done with bio-identical hormone in skin cream or sublingual lozenges, or with synthetic injections.

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From September to June, I see patients in New Smyrna Beach, Florida.
Call 386-409-7747, or send an email to to make arrangements.

In summer, I have a variable schedule, and I see patients in offices at the
Rothfeld Center for Integrative Medicine in Waltham, Massachusetts. For appointments, send an email to make arrangements, or call: 386-409-7747.

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Information herein is not medical advice or direction. All material in this newsletter is provided for information only. Its contents should not be used to provide medical advice on individual problems. Consult a health care professional for medical or health advice.