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February 2011

Sleep lack and stroke and heart risk
Children’s obesity not genetic
Endurance exercise slows aging
Zinc reduces cold symptoms
Vitamin D helps diabetes control
Fish oil helps lung cancer treatment

Sleep lack and stroke and heart risk

Inadequate sleep can be unpleasant and lead to poor performance in daily tasks that require attention and mental agility. It can also increase the risk of both symptoms and mortality from heart disease and strokes. In a review of studies on sleep, researchers evaluated 15 reports covering 474,684 male and female subjects who were followed for 7 to 25 years. During the follow-up time, they found a total of 16,067 cardiovascular events, including strokes and coronary disease (heart attacks and heart deaths). (Cappuccio FP, et al., Sleep duration predicts cardiovascular outcomes: a systematic review and meta-analysis of prospective studies. Eur Heart J. 2011 Feb 7. [Epub ahead of print])

They also evaluated sleep duration for the participants and found that both too little sleep and too much sleep were both associated with increased risks of heart disease and strokes. Those who reported less than six hours of sleep per night had a 48 percent higher risk developing or dying from coronary heart disease, and a 15 percent higher risk of stroke.

In these subjects, those had excessive sleep also had higher risks. They had a 38 percent higher risk of coronary disease or death and a 65 percent higher risk of stroke. While too little sleep is a more common problem, too much sleep is also an issue. These summaries suggested that less than six hours of sleep per night is associated with the higher risks.

One problem with such analyses is the number of variables that can be considered. It is possible that people who get too little or too much sleep might do so as a result of too much caffeine, alcohol, and sugar in the diet, or too little exercise. They might also have psychological problems such as depression or mental illness that not only affect sleep, but also affect diet and other risk factors for cardio-vascular disease and stroke.

Children’s obesity not genetic

Obesity in children is an increasing problem. It may be attributed to less physical activity (more TV and video games, perhaps), and poor diets, and some have suggested that there is a genetic component to obesity. However, the genetic contribution is probably not significant. Genes have not changed dramatically in recent decades but in the past 50 years diet and exercise have changed significantly.

The fact that many meals are eaten outside the home, especially at calorie-laden fast-food restaurants, is part of the problem. These places cater to children’s physical taste preferences and to their entertainment needs (clowns, animated or action figures, etc.). A study of 1003 sixth-grade children in Michigan found that 15 percent of them were obese. The obese children had higher cholesterol levels, as well as higher LDL cholesterol, triglycerides, and blood pressure. (Eagle TF, et al., Health status and behavior among middle-school children in a midwest community: what are the under-pinnings of childhood obesity? Am Heart J. 2010 Dec;160(6):1185-9.)

Obese students consumed more sodas and school lunches than the non-obese, and they were less likely to engage in physical activity. They watched more television and played more video games. None of these lifestyle factors are genetic (although such habits may run in families). To be realistic, the United States is a great melting pot of genes from a variety of countries, but if obesity is not a problem in the countries of origin, it is hard to attribute the rise in obesity to genetics.

Overall, watching TV for 2 or more hours per day was associated with a 19 percent increase in obesity. Consuming school lunches led to a 29 percent increase in obesity (basically, the school lunch program is harmful to kids). Even moderate levels of exercise reduced the incidence of obesity by 11 percent. Attributing these problems to genetics removes the responsibility to teach better lifestyle habits (and set better examples for kids to follow).

Endurance exercise slows aging

A study in mice shows the importance of exercise. In mice with a genetic defect that leads to premature aging that mimics the aging process in humans, exercise was able to markedly slow down the decline. These mice have a defect in mitochondrial function that leads to multi-system pathology in addition to their reduced lifespan.

Human epidemiological studies have shown that endurance training reduces chronic diseases and extends life expectancy, but it is always difficult to draw firm conclusions from such studies. However, it is virtually impossible to do intervention studies in humans that give information on longevity because they would take far too long. A mouse model may not be ideal, but it shows some physiological effects that are informative (especially since we have other evidence that exercise is healthful).

In this study in mice, endurance exercise (treadmill running three times a week) led to an increase of mitochondrial production and prevented the DNA depletion and mutations associated with chronic disease and aging. (Safdar A, et al., Endurance exercise rescues progeroid aging and induces systemic mitochondrial rejuvenation in mtDNA mutator mice Proc Nat Acad Sci 2011, February 22, doi:10.1073/pnas. 1019581108 [epub ahead of print]. The exercise rejuvenated the mitochondria (cellular engines that produce energy), and eliminated the aged appearance and premature mortality seen in similar mice who were not exercising.

Zinc reduces cold symptoms

Zinc supplements have been reported to help reduce cold symptoms and possibly prevent the development of colds, but these conclusions have been controversial. Researchers set out to evaluate the studies from 36 to 44 year databases of research reports to find out if any valid conclusions could be made from randomized, double-blind, placebo-controlled studies. They only included studies that used zinc for at least five days for treatment or five months for prevention. (Singh M, Das RR, Zinc for the common cold. Cochrane Database Syst Rev. 2011 Feb 16;2:CD001364.) Many social and personal benefits would result from anything that helps these symptoms, as colds are one of the leading causes of medical visits and absenteeism from work and school.

They evaluated 13 therapeutic trials with 966 participants and two preventive trials with 394 participants. After seven days of treatment, the zinc groups had 55 percent fewer subjects with symptoms than the control groups. In the long term prevention study, they found that 36 percent fewer colds developed, and there were fewer school absences and antibiotic prescriptions (viral infections such as colds are not treatable with antibiotics, so they are usually overprescribed, but a superimposed bacterial infection might be treated appropriately with antibiotics).

Zinc lozenges need to be given within 24 hours of developing a cold, but they have an unpleasant taste, and can cause nausea. In addition to zinc, other nutrients such as vitamin C can help with colds if given in adequately large doses. Echinacea and garlic might also be helpful.

Vitamin D helps diabetes control

Supplemental vitamin D might help diabetics control their blood sugar. Researchers chose 90 diabetic subjects and allocated them into three groups of 30 to consume twice per day for 12 weeks a plain yogurt drink, a vitamin D-fortified yogurt drink (500 IU of vitamin D), or a vitamin D-fortified yogurt drink with extra calcium (500 IU of vitamin D and 250 mg of calcium). They measured fasting serum glucose (FSG) and glycohemoglobin (HbA(1c) a marker of average blood sugar for 60 days).

Both vitamin D groups had a rise in serum vitamin D ranging from from 28 to 32 nmol/L above baseline. Both vitamin D groups, but not the plain yogurt group, had a reduction in FSG of 10 to 13 mg/dL and a decrease in HbA(1c) of 0.4 percent. They also had an improvement in their marker of insulin resistance. (Nikooyeh B, et al., Daily consumption of vitamin D- or vitamin D + calcium-fortified yogurt drink improved glycemic control in patients with type 2 diabetes: a randomized clinical trial. Am J Clin Nutr. 2011 Feb 2. [Epub ahead of print])

The researchers also measured the serum lipid profile and percent body fat. In both of the vitamin D groups, the waist circumference, body mass index and serum lipids decreased significantly more than in the plain yogurt group. In addition to vitamin D, diabetics are helped by high doses of chromium (1000 mcg/day), vitamin C, alpha lipoic acid, and cinnamon (2 g/day), and ginseng, among others.

Fish oil helps lung cancer treatment

In a small study of non-small cell lung cancer (NSCLC) patients, response to treatment was less than 30 percent. In this research, 46 patients completed the study, 31 given typical care and 15 given the same care plus fish oil (2.5 grams of EPA+DHA combined) per day.

The fish oil group had a 60 percent response rate compared to a 26 percent response rate in the standard care group. After one year, survival was 60 percent in the fish oil group and 38 percent in the standard care group. Cancer patients receiving chemo-therapy often have malnutrition and muscle loss as a result of their disease and the therapy. These researchers had previously shown that fish oil supplements can prevent the muscle loss and fatigue that result from the chemotherapy. (Murphy RA, et al., Supplementation with fish oil increases first-line chemotherapy efficacy in patients with advanced nonsmall cell lung cancer. Cancer. 2011 Feb 15. doi: 10.1002/cncr.25933. [Epub ahead of print]

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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.