A new study confirms the suspicion that increasing vegetable intake lowers the risk of developing aggressive prostate cancers – the kind that spread beyond the prostate into surrounding tissues. (Kirsh VA, et al., Prospective study of fruit and vegetable intake and risk of prostate cancer. J Natl Cancer Inst. 2007 Aug 1;99(15):1200-9.)
In this study of 29,361 men over four years, those who consumed more than one serving per week of cruciferous vegetables (broccoli, cauliflower, Brussels sprouts, and cabbage) reduced their risk by 59 percent, compared to those men who ate these vegetables less than once per month. They did not find an overall lower incidence of prostate cancer, only fewer aggressive ones.
Cruciferous vegetables, also known as the Brassica family, include other vegetables as well, such as kale, collards, broccoli rabe (rapini), turnip greens, mustard greens, bok choy, Chinese cabbage, mizuna, tat soi, and others. Non-brassica cruciferous veggies include arugula, radish, watercress, daikon, and horseradish.
While this study did not show an overall reduction in prostate cancer incidence, I suspect that the reason is their inclusion of anyone over one serving per week in the “high-intake” category. I am curious whether a truly high intake would be more like 3 to 6 servings per week, and whether that level, would indeed lower overall prostate cancer incidence. They are known to reduce lung and colorectal cancer, as well as breast cancer.
Cruciferous vegetables contain sulfur compounds, such as indole-3 carbinol and phenethylisothiocyanates, (glucosinolates) that are known to reduce cancer risk, and other beneficial phytochemicals. These help by reducing DNA damage and by favorably modifying hormone metabolism. They are also rich in vitamin C, fiber, folic acid, vitamin K, and fiber, and contain some omega-3 fatty acids. In addition, broccoli, for example, contains 6 gms of protein for every 50 calories (for comparison, 50 calories from ground beef contains only 4 gms of protein).
Vitamin C and other antioxidants provide important protection against free-radical damage to DNA and cell membranes, and this may be part of the reason that they appear to reduce the risk of cancer. However, this is not their only benefit. Researchers have shown that in mice implanted with human cancer cells, the antioxidants vitamin C and N-acetylcysteine also inhibit the growth of the tumors. (Gao P, et al., HIF-Dependent antitumori-genic effect of antioxidants in vivo. Cancer Cell. 2007 Sep;12(3):230-8.)
The antioxidants apparently reduce the level of a substance that protects tumor cells from attack, and this effect results in growth inhibition.
This information is an important addition to our understanding of how nutrients can work in many different ways. Unlike side effects of drugs, the unexpected effects of nutrients are almost always beneficial. The researchers suggested that this effect might also block colon cancer and cervical cancer growth.
For some inexplicable reason, the researchers cautioned(!) against taking large doses of vitamin C. Increasing evidence supports the value of very high doses of vitamin C in cancer prevention and treatment, as was reported by Linus Pauling decades ago. His position is now being vindicated by the latest research.
Lutein and zeaxanthin are two antioxidant carotenoids that appear to protect the retina from age-related decline. These nutrients are plant pigments that protect the plants and impart to them a yellow to yellow-orange color. A study of 4519 subjects from 60-80 years old showed that over six years, those with the highest level of consumption of these two nutrients had a 35 percent lower risk of macular degeneration than those with the lowest level of intake. (SanGiovanni JP, et al., The relationship of dietary carotenoid and vitamin A, E, and C intake with age-related macular degeneration in a case-control study: AREDS Report No. 22. Arch Ophthalmol. 2007 Sep;125(9):1225-32.) Some of the atrophic retinal changes were reduced by 65 percent.
Lutein and zeaxanthin are found in dark green vegetables such as spinach and broccoli, corn, peas, zucchini (good for gardeners to know in this harvest season), eggs, and romaine lettuce. Supplements of lutein are often derived from the yellow pigment in marigolds, and they usually contain small amounts of zeaxanthin.
The Mediterranean diet appears to provide relief for arthritis sufferers. Patients with rheumatoid arthritis, an autoimmune inflammatory condition of the joints, improved when they were instructed in the benefits of the diet that is rich in fruits, vegetables, beans, fish, and olive oil, and low in red meat and saturated fat. (McKellar G, et al., A pilot study of a Mediterranean-type diet intervention in female patients with rheumatoid arthritis living in areas of social deprivation in Glasgow. Ann Rheum Dis. 2007 Sep;66(9):1239-43.)
Researchers instructed 75 women from 30 to 75 years old with hands-on classes in food preparation for two hours a week for six weeks, backed up by written instructions. Another 55 women were given written instructions only, and all the women were evaluated at the start of the study and again at three and six months for food intake, arthritic symptoms, and overall health assessment.
The women who were given the hands-on classes increased their fruit, vegetable, and legume consumption, and improved the ratio of their intake of monounsaturated oils to saturated fat. The subjects who received only the written instruction did not improve their diets, suggesting the importance of specific instruction rather than just a handout without support.
Symptoms were markedly reduced in the intervention group; their pain score and stiffness were both significantly better and the overall assessment was improved. In addition, the systolic blood pressures were better in this group. The control group had no change in symptoms or blood pressure or their overall health assessment.
Vitamin E has anti-inflammatory, antioxidant, and anti-platelet effects, all of which serve to reduce risks of heart disease, cancer, and inflammatory disorders. A new clinical study shows that supplements of vitamin E help to prevent blood clots in the veins, also called venous thromboembolism, or VTE. (Glynn RJ, et al., Effects of random allocation to vitamin E supplementation on the occurrence of venous thrombo-embolism: report from the Women's Health Study. Circulation. 2007 Sep 25;116(13): 1497-503.)
VTE can lead to strokes and lung blood clots with potentially lethal consequences. Researchers evaluated 39,686 women in the Women’s Health Study, half of whom were given 600 IU of vitamin E on alternate days, and half a placebo. Over 10 years, the vitamin E group had a 21 percent lower risk of VTE than the control group (perhaps they should have taken their vitamin E every day to further lower the risk).
Among the subgroup of women who had a prior history of VTE, the benefits were even greater. Those vitamin E takers had a 44 percent reduced risk of recurrence of the VTE during the same time period. A specific subgroup of women with a genetic propensity to excessive blood clotting had a 49 percent reduction in risk.
Nonetheless, Reuters Health reported that the American Heart Association does not recommend vitamin E supplements to reduce cardiovascular risks. Perhaps the scientific data is not adequately confirmed, but considering the high safety profile of vitamin E, who wants to wait for perfect proof?
Even mild exercise is beneficial when it comes to preventing diabetes. Japanese researchers studied 8600 men who worked for the same company, and evaluated the amount of walking they did to get to work, and then followed them for four years.
The study found that those who walked 21 minutes or more per day to get to work had a 25 percent lower risk of developing diabetes than those who reported walking less than 10 minutes per day. (Sato KK, et al., Walking to work is an independent predictor of incidence of type 2 diabetes in Japanese men: the Kansai Healthcare Study. Diabetes Care. 2007 Sep;30(9):2296-8.)
Exercise improves insulin sensitivity and helps with weight control, both of which are potential contributors to the prevention of diabetes. Of course, exercise has numerous other benefits in prevention of heart disease, improving sleeping patterns, increasing energy and bone density, and elevating mood, and as this study shows, any extra activity helps.
The value of lifestyle changes (diet and exercise) in the prevention and management of diabetes is even more important in light of a recent report on two commonly prescribed diabetes medications, Avandia (rosiglitazone) and Actos (pioglitazone). This meta-analysis of other studies on 14,291 patients taking these drugs showed that they had double the risk of developing heart failure and a 42 percent greater risk of heart attacks compared to those not taking the drugs. (Singh S, et al., Long-term risk of cardiovascular events with rosiglitazone: a meta-analysis. JAMA. 2007 Sep 12;298(10):1189-95.)
Surprisingly, the cardiac risks were present even in younger patients, within a very short time (26 months on the drugs), and even at low doses. Lifestyle changes are free of side effects, and unlike the medications, they are without cost.
Coffee and hypertension
Exercise helps heart patients
Green tea and cancer protection
Antacids damage mental function
Low-normal weight is better
Extra virgin olive oil reduces clotting
Food additives and hyperactivity
Coffee consumption of more than one cup per day appears to increase the risk of hypertension, according to a new study from Finland. Researchers evaluated 24,710 subjects from 25 to 64 years old. Over 13 years, 2505 participants were prescribed medication to treat high blood pressure. (Hu G, et al.,Coffee consumption and the incidence of antihypertensive drug treatment in Finnish men and women. Am J Clin Nutr. 2007 Aug;86(2):457-64.)
The number of patients who had to take blood pressure medication was 25 percent higher among those who drank more than 1 cup of coffee per day. (Among those who drank more than 8 cups per day, the increased risk was not quite as high, but it is not clear why.) Other studies also suggest cardiovascular risks from excessive coffee consumption. The lower risk of diabetes among coffee drinkers in an earlier study was virtually all related to decaffeinated coffee.
Exercise has many benefits, including prevention and treatment of cardiovascular disease. A new study shows that regular exercise for patients with congestive heart failure actually builds new blood vessels and improves function. (Hollriegel R, et al., Regular physical exercise training promotes neovascularization in the skeletal muscle in patients with end-stage chronic heart failure. Eur Heart J (2007) 28 (Abstract Supplement) 745.)
The researchers evaluated 37 patients, half of whom were put on three months of exercise training, 30 minutes per day on an exercise bicycle, and half who were sedentary serving as the controls.
Using muscle biopsies, they found that new blood vessels appeared in the exercising muscles during the three months. They also found a 47 percent increase of circulating stem cells in the blood, adding to the potential for tissue repair and blood vessel generation.
Rather than being afraid to exercise, patients with heart failure (decreased function of the heart muscle) should be encouraged to do physical activity. While they need to stay generally within the limit of their capacity, shortness of breath should not be the limiting factor. A little shortness of breath seems to be the stimulus for the repair process and stem cell formation. Repair and regeneration is the body’s response to the stress.
The lining cells of the arteries are called endothelial cells, and new cells from which the endothelial cells are formed were 130 percent more active in the exercising group compared to both the controls and the activity at the start of the study.
Green tea consumption is associated with a decreased risk of cancer. A new study suggests one possible reason for its benefits. Glutathione S-transferase (GST) is a cancer fighting enzyme produced in the body that helps to detoxify carcinogens.
Researchers administered a standardized extract of green tea containing a specific amount of a polyphenol called epigallocatechin gallate (EGCG; 800 mg daily) to 42 subjects for four weeks. At the end, they found that the subjects with the lowest level of GST had an 89 percent increase in their blood level. (Chow HH, et al., Modulation of human glutathione s-transferases by polyphenon e intervention. Cancer Epidemiol Biomarkers Prev. 2007 Aug;16(8):1662-6.)
While those with the highest levels showed a slight decrease in GST, they were still well protected. The authors concluded that green tea extract supplements (the product they used in their research was decaffeinated) had a beneficial effect in those subjects who had low levels of protection at the start of the study.
Drug companies are particularly fond of drugs that have to be taken regularly for the rest of your life. They make more money on diabetes and hypertension drugs than they do on antibiotics and acute care medications. However, chronic use of many medications leads to problems that are often missed in the shorter term drug-approval process. Thus, many drugs are removed from the market after approval and widespread usage when these effects are discovered (remember Vioxx – an anti-inflammatory found to increase heart problems?).
A new study shows that the use of antacid medications called histamine blockers (H2 antagonists such as Zantac, or ranitidine, and Pepcid, or famotidine) can also have unintended consequences. Researchers studied 1558 African American subjects over 65 years old taking these medications and evaluated them for mental function using an assessment tool called the Community Screening Instrument for Dementia. (Boustani M, et al., The association between cognition and histamine-2 receptor antagonists in African Americans. J Am Geriatr Soc. 2007 Aug;55(8): 1248-53.)
After controlling for a number of variables, they found that those who regularly used antacids such as the ones above had a risk of cognitive impairment that was 2.4 times greater than in those who did not use the drugs. With all the other problems faced by the elderly, if they can manage their symptoms without risky drugs they will be better off.
I often recommend simple dietary changes (more fiber, less fat and sugar, elimination of processed foods, caffeine, and alcohol) and some supplements to manage acid indigestion. The supplements that help include the amino acid L-glutamine, vitamins C and E, aloe vera, and a licorice extract called DGL (chewing tablets of DGL mixes it with saliva and creates a protective coating for the esophagus and stomach).
Among normal weight people who exercise there is an advantage to being in the “low-normal” category of body weight. For 8 years researchers studied 29,139 men and 11,985 women runners, almost all within the limits of normal weight.
Even among these reasonably fit participants, those with higher body mass index (BMI) had a significantly higher risk of developing chronic health problems, such as diabetes, high cholesterol, and high blood pressure. (Williams PT, et al., Weight-related increases in hypertension, hypercholesterolemia, and diabetes risk in normal weight male and female runners. Arterioscler Thromb Vasc Biol. 2007 Aug;27(8):1811-9.)
The lowest risks were associated with BMI between 18.5-20, which is the low end of normal. (Subjects who were excessively thin had somewhat higher risks.) Those men who had a BMI in the 22.5 to 25 range had more than double the risk of diabetes compared to those whose BMI was lower than 20. For women it was a 64 percent increase. The best way to maintain a healthy BMI, in addition to exercise, is to eat a whole, unprocessed diet that is low fat and mostly vegetarian, with a focus on vegetables, fruits, whole grains, beans, seeds, and nuts.
Researchers in Spain evaluated the effects of extra virgin olive oil that is rich in phenols on clotting factors in the blood to see if this might explain its beneficial effects on heart disease. They gave 21 volunteers with high cholesterol one of two breakfasts containing either olive oil with 400 parts per million (ppm) of phenols or an oil with only 80 ppm.
They then measured three different clotting factors and blood lipids two hours after the meal. The high phenol olive oil reduced the excessive clotting risk while the low phenol oil did not. This may explain why some studies of olive oil do not show benefits for heart disease although others do, as olive oils differ markedly in their phenol content. (Ruano J, et al., Intake of phenol-rich virgin olive oil improves the postprandial prothrombotic profile in hypercholesterolemic patients. Am J Clin Nutr. 2007 Aug;86(2):341-6.)
Age, atherosclerosis, and high animal fat in the diet shift the balance of clotting and clot-dissolving factors in the blood to make it more prone to blood clots in the vessels. In this study, factor VII antigen and plasminogen activator inhibitor, both of which promote blood clots, were lowered by the high phenol oil.
Normally, it is better to eat whole foods, and olive oil is an extracted food component. The problem is that olives themselves are cured in brine, and thus they are high in salt, which is too much for many people. In this case, olive flavor is best achieved by using extra virgin olive oil that is high in phenol content.
Over 30 years ago, Dr. Ben Feingold showed that hyperactive children improved when they were put on diets free of artificial flavors, colors, and preservatives. While these substances are not the only contributors to attention deficit hyperactivity disorder (ADHD), it is often a significant part of the problem.
A new study in Britain showed that artificial flavors, colors preservatives (such as sodium benzoate) do indeed contribute to ADHD. (McCann D, et al., Food additives and hyperactive behaviour in 3-year-old and 8/9-year-old children in the community: a randomised, double-blinded, placebo-controlled trial. Lancet 2006 September 6.)
Researchers studied 297 children, either 3 years old or 8/9 years old, and gave half a juice drink with food additives and half the same juice drink without the additives as a placebo.
The additives increased ADHD symptoms significantly in both groups. Even children who did not have ADHD were affected adversely – the additives reduced their attention spans. It is also often helpful to avoid sugar added to foods.
