Exercise, television, and depression
Vitamin C lowers heart failure death
Canned foods increase BPA levels
Fruit lowers uterine fibroid risk
Vitamin D helps cardiac survival
Exercise has been known to help reduce the symptoms of depression. Researchers have published a new report evaluating 49,821 women in the Nurses’ Health Study and the effects of exercise on the risk of depression. They also evaluated the relationship of depression to the amount of television watching among the subjects. All of the subjects were free from depression at the start of the study in 1996. Earlier data on these subjects were obtained in 1992 on the amount of TV that they watched. (Lucas M, et al., Relation between clinical depression risk and physical activity and time spent watching television in older women: a 10-year prospective follow-up study. Am J Epidemiol. 2011 Nov 1;174(9):1017-27.
During 10 years of follow up, they documented 6,505 cases of depression. Higher levels of physical activity were associated with a lower likelihood of developing depression. Those with the highest level of activity had a 20 percent reduction in depression risk compared to those with the lowest level of activity. Reporting was based on physician diagnosis or the use of anti-depressant medications.
In addition to this finding, the researchers noted that those subjects who watched the most television (21 hours per week or more) had a 13 percent increase in the risk of depression. This was independent of the results for physical activity, so those who watch the most TV and at the same time get little exercise are likely to have a 33 percent increase in the risk of depression.
In research presented at the American Heart Association’s Scientific Sessions 2011, low vitamin C intake was associated with higher levels of inflammation and a higher risk of cardiac complications and death among heart failure patients. (As I noted in September, congestive heart failure is a progressive decline in heart muscle function resulting in shortness of breath with physical activity and fluid accumulation outside the blood vessels, primarily in the legs, the lungs, or both.)
Low levels of vitamin C were associated with increased blood levels of C-reactive protein (CRP), a marker of inflammation that is associated with an increased risk of heart disease. Subjects with heart failure and low vitamin C intake were 2.4 times as likely to have high CRP (this is the high-sensitivity CRP test, or hsCRP) as those with the highest vitamin C intake from food. They were also almost twice as likely to die from heart disease within one year of follow-up.
An earlier study evaluated plasma vitamin C levels and the risk of fatal and non-fatal heart failure events. Researchers studied 9,187 men and 11,112 women aged 39 to 79 years as part of the European Prospective Investigation into Cancer and Nutrition (EPIC). They found that for every 20 μmol/L increase in plasma vitamin C concentration there was a 9 percent relative reduction in the risk of heart failure. (Pfister R, et al., Plasma vitamin C predicts incident heart failure in men and women in European Prospective Investigation into Cancer and Nutrition-Norfolk prospective study. Am Heart J. 2011 Aug;162(2):246-53.)
In this study, the high plasma vitamin C related to a diet rich in fruits and vegetables. The highest plasma level led to a 38 percent decline in heart failure. You can achieve this plasma level with vitamin C supplements. However, it is possible that other nutrients in the diet were responsible for some of the benefits.
It is the combination of this data with other research that suggests vitamin C is an important part of the risk reduction. You can achieve even higher plasma levels of vitamin C with higher doses, and these levels might provide even more benefits. More research needs to be done to find this out, but in the meantime the higher doses of vitamin C have other benefits.
Bisphenol A (BPA) is a chemical found in plastics that are used in a wide range of food and beverage containers, mainly those labeled with the recycling number 3 or 7. It is present in the plastic that is used to line food cans and it has been quantified in many canned goods. It is also used in polycarbonate beverage bottles. Urinary BPA levels are correlated with an increase of heart disease and diabetes.
In a study of 75 volunteers, half were given canned vegetarian soup to eat, and the other half were given fresh vegetarian soup made without any canned ingredients. At the end of five days, those who ate canned soup had 12 times more BPA in their urine than the subjects who ate fresh soup. Then the groups were reversed, and again, the canned soup consumers had much more BPA in their urine. (Carwile JL, et al., Canned soup consumption and urinary bisphenol A: a randomized crossover trial. JAMA. 2011 Nov 23;306(20):2218-20.)
Unlike some chemicals, BPA does not appear to persist for a long time in the body after exposure. However, in modern society, exposure is continuous from many different sources (even the thermal printed receipt paper that you get at the cash register). In addition to heart disease and diabetes, BPA is an endocrine disruptor with estrogenic effects and it is especially harmful in early stages of development. It may also affect thyroid function. An earlier study showed a relationship of BPA exposure to obesity.
Fibroids are benign tumors of the uterine muscle. They are also known as leiomyomas. Although they are benign, they can sometimes be large, and in some situations are associated with excessive uterine bleeding as well as pain and discomfort. They can lead to menstrual pain and prolonged menstrual periods, and they often require surgery. Black women have higher rates of fibroids than white women. Researchers in Boston and Philadelphia designed research to find out whether fibroids were related to fruit and vegetable intake and specific nutrients. (Wise LA, et al., Intake of fruit, vegetables, and carotenoids in relation to risk of uterine leiomyomata. Am J Clin Nutr December 2011; 94(6):1620-31.)
They followed 22,583 premenopausal women for 12 years. During that time, they found 6627 cases of fibroid tumors. For those women who consumed the most servings of fruits and vegetables there was a significant drop in the incidence of fibroids. The association was greater for fruits than for vegetables. They were comparing diets with less than 4 servings per week with those that contained at least 2 servings per day.
Vitamin D has been intensively studied in recent years. Although it can be found in the diet, it is made in the body, and is therefore not a true vitamin, but more like a hormone. It is manufactured in the skin from ultraviolet light acting on cholesterol. However, vitamin D production is inadequate for many months of the year in much of the United States and Canada because the sun is just not strong enough. Even in warmer seasons, people do not get enough skin exposure during the day to produce adequate vitamin D (equivalent to 20 minutes per day of full body exposure).
Normal blood levels are considered to be 30 to 100 ng/ml, but many researchers believe that the data suggest that 60 to 100 ng/ml is a better target. Recent research was designed to study vitamin D deficiency and supplementation and the rate of different cardiovascular diseases. Deficiency had already been associated with hypertension, peripheral vascular disease, coronary disease, and heart failure.
Researchers evaluated 10,899 patients averaging 58 years old. The mean serum vitamin D level was 24.1 ng/ml (25-OH vitamin D3). In this subject population, only 30 percent were in the normal range, even by the 30 ng/ml standard. (Vacek JL, et al., Vitamin D deficiency and supplementation and relation to cardiovascular health. Am J Cardiol. 2011 Nov 7. [Epub ahead of print])
Their results confirmed the association of vitamin D deficiency with the cardiovascular conditions listed above. In addition, all-cause mortality was 2.64 times as high in the vitamin D deficiency subjects compared to those with adequate vitamin D. Also, subjects who took vitamin D supplements had a 61 percent lower risk of mortality. In another finding, those with vitamin D deficiency were twice as likely to have diabetes.
Click here to receive the Healthy Living newsletter free.