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Memory, Mind, and Mood
Nutrients improved cognitive function and symptoms of depression in older adults
B vitamins
In earlier studies, B vitamins reduced homocysteine—high levels of which are a factor in Alzheimer’s disease—and slowed brain atrophy, a symptom in those with mild cognitive decline. In this study, 133 people over age 70 with mild cognitive impairment took a daily high-dose B-vitamin supplement containing 800 mcg of folic acid, 500 mcg of B12, and 20 mg of B6, or a placebo. After two years, compared to placebo, homocysteine levels had decreased 30 percent, and executive mental function was stabilized. Those who started the study with the highest homocysteine levels benefited most.
Ginkgo biloba
In this study, 410 people with mild to moderate dementia took 240 mg of ginkgo biloba extract per day or a placebo. After 24 weeks, while there was no change for placebo, the ginkgo group improved greatly in symptoms of apathy and indifference, sleep and nighttime behavior, sudden shifts in emotion, abnormal body movements, and overall mood.
Omega-3
Those with mild cognitive impairment who become depressed are more likely to develop dementia, and doctors said omega-3s may alleviate both cognitive decline and depression. In this study, 50 people over age 65 with mild cognitive impairment and depressive symptoms took a supplement containing mostly docosahexaenoic acid with eicosapentaenoic acid (DHA/EPA), the reverse, or an omega-6 linoleic acid placebo. After six months, compared to placebo, depressive symptoms improved in both omega-3 groups. In addition, the DHA/EPA group also had better verbal fluency and better self-reported physical health. The DHA/EPA supplement contained 1,550 mg DHA plus 400 mg EPA.
Reference: International Journal of Geriatric Psychiatry; 2011, Electronic Prepublication
Chocolate Linked to Healthier Hearts
Researchers reviewed six studies that tracked all forms of chocolate in the diet. Participants reported how often they ate chocolate, from never to more than once per day. Overall, compared to those with the lowest levels, those with high levels of chocolate in the diet—in all forms—were 29 percent less likely to have a stroke and 37 percent less likely to develop cardiovascular disease. While one should be aware of the high calories of some chocolate confections, doctors said that cocoa contains flavonols and has antioxidant, anti-inflammatory, and anti-clotting properties, which may help prevent cardiometabolic disorders.
Reference: British Medical Journal; August, 2011, Electronic Prepublication
Recipe: Chocolate Rice Pudding
Breast Health
Nutrients lower chances of developing breast cancer, and increase survival in those with the disease
Vitamin D
Doctors said earlier studies suggest breast cancer chances increase when vitamin D levels are low. In this study, researchers measured vitamin D in the diets of 3,101 pre-and post-menopausal women with breast cancer, aged 25 to 75, and compared them to 3,471 cancer-free women of similar ages, backgrounds, and menopausal status.
Overall, while there was no link between breast cancer and vitamin D from food, pre- and post-menopausal women who took a vitamin D supplement of more than 400 IU per day were 24 percent less likely to develop breast cancer compared to women who did not take a vitamin D supplement.
Although the study could not measure vitamin D in adolescence, researchers suggested that taking a vitamin D supplement during these formative years may be the most important factor in preventing breast cancer.
Lignan phytoestrogens
Flax and other seeds, vegetables, and wheat contain lignan phytoestrogens, hormone-like compounds which earlier studies found protected against cancer. In this study, researchers measured enterolactone, the form lignans take in the blood, in 1,140 postmenopausal women with breast cancer. After six years of follow-up, compared to those with the lowest levels, women with the highest lignan levels were 42 percent more likely to have survived, and their cancer was similarly less likely to have progressed.
Reference: Journal of Clinical Oncology; 2011, Vol. 29, No. 28, 3730-8
The Vitamin D Debate
New research explores raising levels to increase longevity and reduce disease, and tailoring recommendations to specific populations
Raising levels worldwide may prolong life
In a review of worldwide vitamin D and major disease studies, researchers estimated that by raising blood levels of vitamin D to 44 nanograms per milliliter of blood (ng/mL) from 20 ng/mL currently, annual worldwide deaths from major diseases would decrease by 20 percent, and increase average life expectancy by two years. According to study authors, vitamin D lowers chances of and increases longevity in the five major disease groups that account for over half the world’s mortality rates. These include cancer, cardiovascular disease, diabetes, tuberculosis, and respiratory diseases and infections. Doctors said to raise vitamin D levels, manufacturers should fortify foods, and people should take vitamin D supplements and get more sunlight.
One size doesn’t fit all
Doctors said that recommendations to prevent vitamin D deficiency should consider physical and environmental factors. In this study, researchers measured vitamin D levels in 492 men aged 40 to 79, living in Chicago, a low-sunlight region, and found that 93 percent of African American men and 70 percent of European American men were deficient, with levels below 30 ng/mL. Doctors said that the melanin in dark skin blocks ultraviolet rays, reducing the amount of vitamin D the body can produce from sunlight. Because there are many special populations in the U.S.; those with darker skin, those who customarily cover their skin, and those who live in low-sunlight areas, the government should provide more than one recommendation for the proper dietary level of vitamin D, researchers concluded.
Reference: European Journal of Clinical Nutrition; 2011, Vol. 65, No. 9, 1016-26
Cancer Update
Nutrients lower chances of cancer and inhibit cancer growth
Glucosamine
Inflammation plays an important role in developing lung cancer, and previous studies have linked anti-inflammatories such as glucosamine, chondroitin, and non-steroidal anti-inflammatory drugs (NSAIDs) to lowering the chances. In this study, researchers asked 76,904 people to report the glucosamine, chondroitin, and NSAIDs they had taken during the previous 10 years. Doctors found no links to chondroitin or NSAIDs, but compared to those who did not take glucosamine, those who had taken glucosamine at least four days per week for at least three years were 51 percent less likely to develop lung cancer (adenocarcinoma).
Curcumin
Researchers thought curcumin might work in the mouths of people with head and neck malignancies to reduce activities that promote cancer growth. In this pilot study, 21 people with head and neck cancers gave saliva samples before and after chewing two curcumin tablets containing a total of 1,000 mg of curcumin. Curcumin suppressed a signaling process that tells cancer cells to grow, and reduced inflammatory molecules in the saliva that promote cancer growth.
“The curcumin had a significant inhibitory effect, blocking two different drivers of head and neck cancer growth,” doctors said, going on to suggest that curcumin could combine with other treatments such as chemotherapy and radiation to treat head and neck cancers, and might help prevent these cancers in tobacco smokers and chewers, as well as help prevent the recurrence of oral cancers.
Although turmeric, which contains curcumin, is a common cooking spice, the dosage to achieve a clinical effect is much higher. Researchers are planning a longer study, beginning a few weeks before cancer surgery, to see if curcumin produces a larger inhibitory effect.
Reference: Cancer Causes and Control; 2011, Vol. 22, No. 9, 1333-42
Early-stage nutrition discoveries: Metabolic Syndrome, Antioxidants
Good results in the lab can lead to larger human trials. Here are some of the most promising recent findings.
Metabolic syndrome
Lack of adequate oxygen during gestation restricts growth and increases the chances of metabolic syndrome later in life. Resveratrol helps sensitize the body to insulin, and doctors in this study wanted to see if resveratrol could prevent metabolic syndrome in those born with restricted growth. After weaning, growth-restricted male rats ate a high fat diet alone or with resveratrol. After nine weeks, those on resveratrol had less severe metabolic syndrome, including better glucose tolerance, less insulin resistance, reduced abdominal fat, and fewer total circulating fats.
Antioxidants in hazelnuts
Researchers in this study analyzed the amount of antioxidant polyphenols in the skins of hazelnuts, from several samples. Doctors wanted to find the total antioxidant capacity (TAC); the ability to neutralize the oxygen free-radicals that cause oxidative damage. TAC is a way to compare the antioxidant power of different types of foods. The hazelnut skins had TAC about three times that of whole walnuts, seven times that of dark chocolate, 10 times that of espresso coffee, and 25 times that of whole blackberries.
Reference: Journal of Agricultural and Food Chemistry; 2011, Vol. 59, No. 18, 9935-41
Combating Colds
A review of 44 years’ worth of cold studies finds nutrients help
Vitamin C
Combining findings from all vitamin C studies, the most consistent evidence suggests that taking 1,000 mg of vitamin C per day shortened colds by 8 percent in adults and 18 percent in children, or by 1.5 to 2 days. In a subgroup of six studies, 642 people were exposed to severely stressful arctic cold or intense physical activity. Those who took 200 mg to 2,000 mg of vitamin C per day had half as many colds as placebo. Doctors believe vitamin C stimulates infection-fighting white blood cells.
Echinacea
In lab studies, echinacea activated white blood cells that produced antibodies to fight bacteria and viruses. Echinacea purpurea is the most common form of echinacea. In four of six echinacea purpurea studies, 764 healthy adults with cold symptoms who took echinacea saw milder symptoms compared to placebo, and colds shortened by 1.5 to 4 days.
Garlic
Researchers said allicin is the active agent in garlic that causes its odor and contains antiviral properties. In one study of 146 healthy adults during 12 weeks of winter, those who took 180 mg of allicin extract per day had 64 percent fewer colds compared to placebo.
Zinc
Zinc is an essential mineral which, when deficient, raises chances for infection. In four of five studies using 13 to 23 mg of zinc lozenges every two hours, participants saw milder symptoms and colds shorten by 1.3 to 6.9 days. In 13 zinc lozenge studies, while there was no effect in five of the studies that used less than 75 mg of zinc per day, in five studies that used more than 75 mg of zinc salts per day, colds shortened by 20 percent, and in three studies using more than 75 mg of zinc acetate per day, colds shortened by 42 percent.
Reference: Canadian Family Physician; 2011, Vol. 57, No. 1, 31-6
Healthy Insight
Purple Potatoes Lower Blood Pressure
The dark pigment in purple potatoes is rich in blood vessel-relaxing phytochemicals, according to doctors, and in this study, 18 overweight or obese people with high blood pressure microwaved seven golf-ball sized purple potatoes with skins on and no fat, or a potato starch placebo, twice per day. After one month, while there was no effect for placebo, purple potato eaters had not gained weight and saw systolic and diastolic blood pressure ease 3.5 and 4.3 percent, respectively, including in those also taking blood pressure medications. Potatoes of all colors are low in calories and rich in healthful phytochemicals and vitamins.
Recipe: Dilly Baby-Blues - delicious and good for you, too!
Reference: Meeting of the American Chemical Society; August, 2011, Denver, Colo., Vinson, Joseph, PhD
Cancer Update
Nutrients may extend life in, and lower chances of, certain cancers
Antioxidant vitamins
In this study, doctors measured vitamin and mineral supplementation in 23,943 men and women without pre-existing cancer, heart attack, or stroke. After 11 years of follow-up, compared to those who did not take supplements, those who were regularly taking antioxidant vitamins when the study started were 42 percent less likely to have died from any cause and 48 percent less likely to have died from cancer.
There were several differences between supplement users and non-users. Those who took supplements tended to be more physically active, have a healthier diet with more fruits, vegetables, and milk, and less meat and processed meat products, and were more likely to be college-educated older women.
Garlic, grape seed, and multivitamins
Researchers said there is increasing evidence that the nutrients in fruits and vegetables may protect against cancers of the blood, bone marrow, and lymph (hematologic), and in this study wanted to test nutritional supplements. Doctors measured the vitamins, minerals, and specialty supplements in the diets of 66,227 healthy men and women, aged 50 to 76. After eight years of follow-up, compared to those who did not take these supplements, those who took a daily multivitamin for at least eight years were 20 percent less likely to develop a hematologic cancer; for grape seed extract, 43 percent less likely; and for those who took garlic supplements at least four days per week for three or more years, 45 percent less likely.
Reference: European Journal of Nutrition; June, 2011, Electronic Prepublication
Blood Pressure Update
Nutrients help lower blood pressure
Soy and milk proteins
In this study, 352 adults with high blood pressure (BP) of 120-159/80-95 mmHg, took 40 grams per day of soy protein, milk protein, or a carbohydrate placebo, in three 8-week cycles, with three week’s rest in between each phase. Researchers measured BP twice at the start and end of each phase and found, compared to placebo, systolic BP was 2.0 mmHg lower during the soy protein phase, and 2.3 mmHg lower during the milk protein phase.
Natural nutrients
In a review of 84 blood pressure studies, doctors said that even though there are many pharmaceutical options for reducing BP, it is very important also to exercise more, reduce salt and calories, eat more fruits, vegetables and fiber, and decrease fats. Among the findings:
Calcium: Those who took a calcium supplement had a mild decrease in BP. Doctors said calcium helped blood vessels relax.
Coenzyme Q10: In a review of several CoQ10 studies, systolic BP was 16 mmHg lower on average for CoQ10 compared to placebo.
Flavonoids: Diets high in cocoa appeared to lower systolic BP by 3 to 5 mmHg.
Folate: Those whose diets are low in folate are more likely to have elevated BP, and women who took folic acid supplements were less likely to have high BP.
Garlic: Several studies showed garlic extract lowered BP 10 to 16 mmHg.
Potassium: Diets low in potassium can cause a rise in blood pressure.
Vitamin D: People with high BP were more likely to have low levels of vitamin D compared to those with normal BP, and systolic BP decreased 2.4 mmHg after taking a vitamin D supplement.
Reference: Circulation; 2011, Vol. 124, No. 5, 589-95
Healthy Babies
Nutrients help ensure healthy, normal size, full-term babies
Multivitamins reduce chances of preterm births
Doctors said about one in eight U.S. babies is born prematurely—before 37 weeks—and in this study wanted to see if taking multivitamins just before or after becoming pregnant could reduce small-for-gestational-age and preterm babies. In the study, 35,897 women reported the multivitamins they took during the six weeks just before and six weeks after becoming pregnant. Compared to women who did not take multivitamins, women with pre-pregnancy body mass index (BMI) scores no higher than 25 who took multivitamins regularly before and after becoming pregnant were 16 percent less likely to have a preterm birth, and 20 percent less likely to have preterm labor. Women of any BMI who took multivitamins before and after becoming pregnant were 17 percent less likely to have babies that were small for their gestational age.
Omega-3 and healthy infants
Researchers in this study gave 1,100 pregnant women a placebo or 400 mg of docosahexaenoic acid (DHA) from seaweed per day, from 18 to 22 weeks pregnant through childbirth. Compared to placebo, at one month of age, children whose mothers took DHA had shorter colds and 25 percent fewer symptoms such as coughing, wheezing, and phlegm. At three months, DHA kids spent 14 percent less time ill. At six months, DHA kids had longer vomiting episodes, but 20 to 25 percent shorter fevers, less difficulty breathing, and less rash.
Reference: American Journal of Clinical Nutrition; 2011, Vol. 94, No. 3, 906-12
Preserving Eyesight
Nutrients help stabilize and protect the eyes
Goji berry protects the macula
The macula of the eye concentrates the yellow carotenoid pigments lutein and zeaxanthin which filter and absorb harmful short-wavelength blue light. With age, the macula thins and dries out, leaving areas without pigment, and fatty deposits nearby, two signs of age-related macular degeneration (AMD); the loss of sight in the center of the field of vision.
Goji berry is rich in lutein and zeaxanthin, and in this study, 150 healthy participants, aged 65 to 70, took 1,370 mg of a goji berry formula per day, or a placebo. After 90 days, the placebo group had lost pigmentation and increased fatty deposits compared to the start of the study, while the goji berry group remained stable. And while the placebo group did not change, the goji berry group saw blood levels of zeaxanthin rise by 26 percent, and antioxidant capacity increase by 57 percent.
Lutein increases macular pigment
Researchers said several large clinical trials had shown that macular pigment declines as lutein in the diet decreases, raising the chances for AMD. In this study, 126 people with AMD took lutein or a placebo. After six months, macular pigment optical density—a measure of pigment thickness—increased 28 percent compared to placebo, and the lutein group had better visual perception and clarity.
Reference: Optometry and Vision Science; 2011, Vol. 88, No. 2, 257-62
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