Diet in youth may determine heart risks
Curcumin inhibits cancer cell growth
Mediterranean diet preserves the brain
Vitamin E from diet is insufficient
Low serum selenium raises mortality risk
Researchers set out to study the relationship between the intake of fruits and vegetables (F/V) in young adulthood to the risk of developing coronary atherosclerosis later in life. In this report, they evaluated data from the Coronary Artery Risk Development in Young Adults (CARDIA) study, including young, healthy black and white individuals from the start of the study in 1985-1986. They had 2506 participants, of whom 63 percent were female. The average age at baseline was 25 years old. F/V intake at baseline was evaluated with an interview-administered semi-quantitative dietary history.
They divided the group into thirds based on low, medium, or high intake of F/V, and then followed the subjects for 20 years. At the end of the study, they measured the degree of coronary artery calcification using a CT scan. Coronary artery calcification is an indicator of risk of coronary atherosclerosis. Female subjects at the high end of F/V intake consumed about 9 servings per day, while men in the high end consumed 7 servings per day. Among subjects in the lowest third, women consumed 3.3 servings and men just 2.6 servings per day.
At the end of 20 years, those with the highest intake of F/V had up to a 26 percent reduction in the level of coronary calcification. After adjusting for other dietary variables, the reduction was still a highly significant 16 percent lower risk. When they considered fruits and vegetables separately, the results were similarly beneficial for each of them. The authors concluded that their results reinforce the importance of establishing good habits of fruit and vegetable intake early in life, rather than waiting for a problem to develop and then changing to a healthier diet. (Miedema, M, et al., The association of fruit and vegetable consumption during early adulthood with the prevalence of coronary artery calcium after 20 years of follow-up: The CARDIA Study. Circulation 114.012562 published online before print October 26, 2015.)
When I look at what most young (and older) people are eating, I realize that doctors will never be short of patients. It is not news to my readers that I recommend a diet that is at the highest end of fruit and vegetable intake, plus whole grains, legumes, seeds and nuts. This leaves a wide variety of tasty and attractive foods to satisfy any palate.
Curcumin is a polyphenol phytochemical, found in the spice turmeric. It has anti-inflammatory and antioxidant properties, it reduces liver toxicity from a number of chemicals, it reduces the clumping of platelets (atherosclerosis protection), and it may protect against the metastasis of melanoma. In addition, it is thought to be one contributor to unusually low rates of Alzheimer’s disease in India, where they eat a lot of turmeric-containing curry.
I noted the benefits of curcumin for depression and cancer in my last newsletter, and now a new laboratory study suggests that curcumin is a valuable adjunct to chemotherapeutic agents in treatment of colorectal cancer. In this study, researchers used patient-derived colorectal cancer liver metastases to assess the difference between the chemotherapy alone or in combination with curcumin. Addition of curcumin to the chemotherapy agents 5-fluorouracil and oxaliplatin enhanced the anti-proliferative and pro-apoptotic (programmed cell death) effects.
Curcumin alone and in combination with the chemotherapy reduced certain cellular tumor markers. In the phase I dose escalation trial, curcumin was found to be both safe and tolerable in patients with colorectal cancer liver metastases, even at doses up to 2000 mg per day. (James MI, et al., Curcumin inhibits cancer stem cell phenotypes in ex vivo models of colorectal liver metastases, and is clinically safe and tolerable in combination with FOLFOX chemotherapy. Cancer Lett. 2015 Aug 10;364(2):135-41.)
These are unchanged from the last issue. I still take about 500 mg of curcumin twice per day unless I am eating curry that day (which is fairly frequent, but not as much as they eat in India).
In a review article, researchers analyzed the relationship of sugar-sweetened beverages, artificially-sweetened beverages, and fruit juice to the incidence of type 2 diabetes. They only examined prospective studies using national surveys in the United States (covering 189 million adults without diabetes) and in the United Kingdom, (covering 44 million people). They included data from studies published up until 2014.
Higher consumption of sugar-sweetened beverages was associated with a greater incidence of type 2 diabetes by 18 percent per serving per day, and 13 percent after adjusting for adiposity (meaning that the diabetes risk was not all attributable to weight gain). For artificially sweetened beverages, the risk increase was 25 percent per serving, but after adjusting for adiposity, the risk increase was only 8 percent (suggesting that obesity is associated with both diabetes risk and higher consumption of artificially sweetened drinks). For fruit juice, the risk increase was almost all attributable to obesity, not the drinks themselves.
The authors estimated that over a 10-year period, about 10 percent of the cases of diabetes could be attributed to consumption of sugar-sweetened beverages. They also noted that neither artificially sweetened drinks nor fruit juice were likely to be healthy alternatives to sugar-sweetened beverages.
Those people who drink sugar-sweetened beverages are unlikely to heed this message, but it is important to repeat it for those few who might. It is unclear from this article that fruit juice is much better, but it certainly has a greater likelihood of providing at least some nutrition. The problem is that most fruit juice is as sweet as many sugar-sweetened beverages. My suggestion is to use fruit juice only if it is very diluted. I’ll use it just to flavor water or sparkling water, with only about 10 to 15 percent juice.
It is desirable to get as many nutrients and phytochemicals as possible from a healthful diet. However, some nutrients are beneficial when taken in amounts that are difficult to get from diet alone. Vitamins C and D are two examples, even if someone chooses a very healthful diet. Some other nutrients and phytochemicals have specific benefits for protection from the effects of environmental exposures (pollution; excessive sunlight), stress, and the genetic predisposition to certain conditions (however, genetic predisposition to diseases is much less of a contributor than unhealthful lifestyle choices, such as poor diet, smoking, excessive alcohol consumption, and lack of exercise). Because most people in the United States do not consume an ideal diet, supplements may be even more important.
A new study shows that with the US diet, vitamin E is a nutrient that is inadequate from dietary sources alone. Vitamin E is a fat-soluble antioxidant that protects cell membranes from free-radical damage, and low blood levels have been associated with increased mortality and higher rates of heart disease. Researchers called vitamin E a “shortfall nutrient” because over 90 percent of American adults do not consume recommended amounts. Vitamin E adequacy is reflected in serum levels greater than 30 micromol per liter (μmol/L), while deficiency is considered to be a level below 12 μmol/L.
In this analysis, based on the National Health and Nutrition Examination Survey (NHANES, 2003-2006), the researchers aimed to determine the prevalence of both clinical vitamin E deficiency and failure to meet vitamin E adequacy. Only a small proportion of the population was considered to be clinically deficient. However, the average serum levels of those whose vitamin E came from food alone was only 24.9 μmol/L. Those whose intake of vitamin E came from both food and dietary supplements had an average serum level of 33.7 μmol/L.
They found that among persons 20 to 30 years old 87 percent had inadequate vitamin E levels. Among those subjects over 51 years old, 43 percent had inadequate serum vitamin E status. The difference between those whose vitamin E came from food alone compared to those who consumed both food and supplements were consistent across age, sex, and race/ethnic groups. (McBurney MI, et al., Suboptimal serum α-tocopherol concentrations observed among younger adults and those depending exclusively upon food sources, NHANES 2003-20061-3. PLoS One. 2015 Aug 19;10(8):e0135510).
Foods are generally very low in vitamin E. the best food sources are sunflower seeds and almonds, but the best sources per calorie are spinach, beet greens, asparagus, mustard greens, and Swiss chard. Vitamin E occurs in food in alpha, beta, gamma, and delta tocopherol. Gamma tocopherol is the most abundant in the diet and has some benefits that are not available from alpha tocopherol. I take a high-gamma tocopherol supplement (400 IU per day). Vitamin E is extremely safe even in high doses, and 3000 IU per day have been administered with no side effects. Some research has shown that 2000 IU per day of tocopherol can slow the progression of Alzheimer’s disease. High doses of coenzyme Q10 have similar benefits, and may also help to delay the progression of Parkinson’s disease.
Selenium (Se) is an essential dietary trace mineral that has antioxidant properties. It is necessary for the activity of the antioxidant enzyme glutathione peroxidase. It also helps to recycle vitamin C. It may play a role in the prevention of cancer. The healthiest sources of Se are whole grains and seeds, as well as Brazil nuts, which are exceptionally rich in the mineral. In terms of nutrient density (amount of the nutrient per calorie) Crimini mushrooms (young versions of Portabella mushrooms) have the most selenium.
A recent study shows that an adequate serum level of Se has health benefits. Researchers in Sweden evaluated 668 elderly participants and measured their serum Se and then followed them for 6.8 years. Their mean serum level was 67 micrograms per liter (μgm/L). This corresponded to a relatively low selenium intake, despite decades of nutritional information campaigns by the Swedish government for improvement of public health.
At the end of the study, they correlated mortality from all causes and from cardiovascular disease with serum Se levels. Those in the lowest quartile of Se level had a 43 percent higher mortality from all causes compared to those in the highest quartile of serum Se. For cardiovascular mortality they found a 56 percent increased mortality risk. (Alehagen U, et al., Relatively high mortality risk in elderly Swedish subjects with low selenium status. Eur J Clin Nutr. 2015 Jun 24. doi: 10.1038/ejcn.2015.92. [Epub ahead of print]
The same group of researchers previously published a 5-year prospective study showing significant reduction in cardiovascular mortality after supplementation with selenium and coenzyme Q10. The treatment group mortality was less than half of that in the placebo group (5.9 percent versus 12.6 percent). (Alehagen U, et al., Cardiovascular mortality and N-terminal-proBNP reduced after combined selenium and coenzyme Q10 supplementation: a 5-year prospective randomized double-blind placebo-controlled trial among elderly Swedish citizens. Int J Cardiol. 2013 Sep 1;167(5):1860-6. doi: 10.1016/j.ijcard.2012.04.156. Epub 2012 May 23.)
Selenium is in many foods, but the quantity depends on where the food is grown. Although our food supply comes from all over the country (and indeed the world), in regions where soil selenium is low (such as New England, the Southeast, the lower part of the Southwest, and the Northwest states), selenium intake from food is commonly low. Soil selenium is only high in the upper Midwest, the Dakotas, Montana, and Colorada, and isolated other areas. I take a supplement of 200 mcg per day, and this amount is found in many multivitamin and mineral combinations, as well as single supplements. Seleno-methionine (bound to the amino acid methionine) is a common supplement, and relatively well absorbed.