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March 2007
February 2007
January 2007
Healthy skin
The antioxidants beta carotene, lutein, lycopene, selenium, vitamin E, and zeaxanthin improved skin health in two new studies. Researchers divided 39 volunteers with healthy, normal type 2 skin—fair skin that burns easily and tans minimally—into three groups. The first group took 4.8 mg of beta carotene, 3 mg of lutein, 3 mg of lycopene, 75 mcg of selenium, and 10 mg of vitamin E (alpha tocopherol) per day. The second group took no lutein, 6 mg of lycopene, and the same dosages of the other three supplements per day, while the third group took a placebo.
After 12 weeks, while the placebo group had not improved, both supplement groups had higher blood-fluid (serum) levels of antioxidants; thicker, denser skin as measured by ultrasound; and less rough and scaly skin, which doctors measured using ultraviolet light.
The Journal of Skin Pharmacology and Physiology will also publish new findings later in 2007 from the University of Naples, Italy, where researchers studied the effects of lutein and zeaxanthin on female subjects, aged 25 to 50. Subjects took an oral supplement of 5 mg of lutein and 0.2 mg of zeaxanthin, twice per day, for a daily total of 10 mg of lutein and 0.4 mg of zeaxanthin. The women also applied a treatment to the surface of the skin (topical) that contained 50 parts-per-million (ppm) lutein and 2 ppm zeaxanthin per day, supplying 50 mcg of lutein and 2 mcg of zeaxanthin per gram of topical treatment.
Every two weeks for 12 weeks, researchers measured skin moisture (hydration), ability to maintain size and shape (elasticity), protective fat layer (superficial skin lipids), and cell membrane damage (lipid peroxidation), and found that, compared to placebo, those who had taken lutein and zeaxanthin orally, topically, alone or together, had significantly improved in each measure. The oral-topical combination group averaged 60% greater hydration, 20% better elasticity, 50% more lipid protection, and 64% less cell damage.
Reference: Skin Pharmacology and Physiology; 2006, Vol. 19, 224-31.
Better blood circulation
Pycnogenol®, the antioxidant extract of French maritime pine bark, improved blood-circulation disorders in three new studies. Doctors assigned 30 diabetic patients with severe blood-vessel damage and ulcers on the lower limbs to take an oral 150 mg dose of Pycnogenol, a topical 100 mg dose of Pycnogenol powder (from the capsule) applied directly to the wound, a combination of these two treatments, or a placebo, per day for six weeks. All four groups also washed the wound with warm water and disinfected each day.
At the end of the study, the oral-topical combination group had a 74.4% decrease in the size of the ulcer, the oral group had a 41.3% decrease, the topical group had a 33% decrease, and the placebo group had a 22% decrease in ulcer size. Those who took oral Pycnogenol also had better blood circulation in the small blood vessels (microcirculation).
In an eight-week study, 21 patients aged 42 to 60—11 men, 10 women—with inadequate blood flow in the veins of the limbs and ankle swelling (together, severe venous hypertension), and a history of chronic leg wounds (venous ulcerations) took 150 mg of Pycnogenol per day, while doctors observed 18 similar patients who received no treatment (control group). At four weeks, and at the end of the study, doctors found that those who had taken Pycnogenol had fewer symptoms of bleeding in small blood vessels (microangiopathy), less fluid leaking from the smallest blood vessels (capillary filtration), and less fluid accumulating in the space between cells (edema), while there were no changes in the control group.
People who take high-blood-pressure medication (anti-hypertensive) may suffer from edema. In this eight-week study, researchers gave Pycnogenol to hypertensive patients who were taking one of two types of anti-hypertensive drug: nifedipine or an angiotensin-converting enzyme inhibitor; and found that capillary filtration decreased significantly. Doctors concluded that in hypertensive patients, Pycnogenol controls this type of edema, helps prevent damage in the microcirculation, and allows doctors to reduce the dose of anti-hypertensive drugs in most patients.
Reference: Journal of Clinical and Applied Thrombosis/Hemostasis; 2006, Vol. 12, No. 3, 318-23.
Increasing energy
The antioxidant alpha lipoic acid (ALA) improved the ability of the body to absorb and convert sugar (glucose) to energy (glycemic control-insulin sensitivity) in type 2 diabetes mellitus, according to a new study. Researchers recruited 12 obese type 2 diabetics, average age 53, and gave an oral dose of 600 mg of ALA, twice per day for a daily total of 1,200 mg of ALA, for four weeks. Doctors also monitored, as a control group, 12 healthy subjects with normal glucose tolerance and insulin sensitivity who did not take ALA.
At the end of the study period, scientists found that the diabetics were able to clear glucose from the blood nearly twice as quickly—an average 85.8% increase in clearing rate—as before taking ALA. The doctors also determined how sensitive the diabetics were to insulin—the natural hormone produced by the healthy body that regulates glucose—and found that insulin sensitivity increased 62.3% after taking ALA. The scientists noted that there was no statistically significant difference in insulin sensitivity between the diabetics who had taken ALA and the healthy control group, leading the doctors to conclude that short-term oral ALA treatment increases insulin sensitivity in patients with type 2 diabetes mellitus.
Prior studies have shown that ALA improved insulin sensitivity when patients received an injection of the antioxidant, and doctors wanted to determine if ALA would be as effective entering the system through the digestive tract.
Reference: Hormones (Athens, Greece); October-December, 2006, Vol. 5, No. 4, 251-8.
Think omega-3
Omega-3 and omega-6 polyunsaturated fatty acids and the antioxidant asthaxanthin helped improve memory and attention, and delay mental decline (cognitive impairment) in two new studies. Japanese researchers gave 21 patients with mild cognitive impairment—average age 68, 9 females, 12 males—a 240 mg combination of omega-3 (docosahexaenoic acid, or DHA) and omega-6 (arachidonic acid, or ARA) fatty acids, plus 0.96 mg of asthaxanthin, in six 40.16 mg capsules per day, or a placebo, for 90 days.
Ten of the subjects had prior brain injury—lesions due to hemorrhage or trauma—and eight had been diagnosed with early Alzheimer’s disease (AD). The scientists measured mental function at the start and end of the study and found that brain-injury patients who had taken the supplements had significantly improved immediate and delayed memory, and significantly increased attention, while AD patients who had taken supplements, and those in the placebo group, had not improved significantly. Doctors said the results suggest that omega-3, omega-6, and asthaxanthin can improve cognitive function in the aged, and in those with brain lesions.
In October, 2006, Swedish researchers reporting in the Archives of Neurology randomly gave 174 AD patients—with very mild, mild, or moderate cognitive impairment—1,700 mg of DHA plus 600 mg of eicosapentaenoic acid (EPA) per day, or a placebo, for six months. When researchers measured results for the entire group, there were no significant differences between treatment and placebo.
However, in a subset of 32 AD patients with very mild cognitive impairment, those who had taken omega-3s had significantly less mental decline compared to those who had taken the placebo. After six months, the entire placebo group switched to the omega-3 treatment, and all participants continued for a second six-month period. Doctors found that those with very mild cognitive impairment who had switched to omega-3 from placebo had significantly less mental decline in the second six-month period compared to the first six months.
Reference: Neuroscience Research; 2006, Vol. 56, 159-64.
Calcium and cancer risk
A large, new Chinese study has found that calcium protects against cancer of the colon and rectum (colorectal). The Shanghai Women’s Health Study, from 1997 through 2000, enrolled 73,314 Chinese women aged 40 to 70, average age 55.5, who were living in urban Shanghai. Researchers followed up for an average of 5.7 years and, excluding the first two years of follow up, found that those with the highest amounts of calcium in the diet were 40% less likely to develop colorectal cancer than were those with the lowest dietary calcium. By the end of the follow up period, there were 129 reported cases of colon cancer, and 91 reported cases of rectal cancer.
The study is significant because of the large number of participants, and because the Chinese diet typically includes less calcium than does the Western diet. Previous large U.S. studies: the 1991 Women’s Health Initiative with 161,808 women, the 1976 Nurse’s Health Study I with 122,000 women, and the 1989 Nurse’s Health Study II with 125,000 women, did not report any link between calcium and colorectal cancer.
As in those studies, doctors in the Shanghai survey asked participants to fill out a food-frequency questionnaire, covering 77 foods representing 90% of the typical diet. Researchers also calculated the amounts in the diet of vitamins A, B1, B2, B3, C, and E, as well as carotene and fiber, and found no link to risk for colorectal cancer. The scientists concluded that calcium appears to protect against colorectal cancer, even at the relatively low levels in the Chinese diet compared to the Western diet. Colorectal cancer is one of the most curable cancer types, and doctors can diagnose the disease easily and early using a colonoscopy exam.
Reference: International Journal of Cancer; 2006, Vol. 119, No. 12, 2938-42.
News! An apple a day…
Apples contain powerful antioxidant nutrients called phytochemicals which doctors believe reduce risk for asthma, certain cancers, type 2 diabetes, and heart and blood vessel (cardiovascular) diseases, according to a review of the most recent research. Doctors found that, in lab tests compared to other fruits and vegetables, apples reduced cancer-cell growth (proliferation), cut fat-cell (lipid) and DNA damage (oxidation), and lowered cholesterol. Other studies showed that those who ate apples had improved lung function, and lost more weight than did those who had not eaten apples. The scientists noted that the phytochemicals in apples readily penetrate the tissues of the body (bioavailability), and fresh, unprocessed apples and apple peels contain the most phytochemical activity.
Reference: Nutrition Journal; May, 2004, Vol. 3, No. 5.
Better bones
Folic acid (vitamin B9), vitamin B12, magnesium, and potassium citrate improved bone health in several new studies on men, women, and children. A study in the European Journal of Clinical Nutrition found that folic acid combined with vitamin B12 reduced homocysteine, a chemical compound that doctors believe increases risk for bone disease (osteoporosis) and fracture. Researchers reporting in the New England Journal of Medicine followed nearly 2,000 patients with osteoporosis, aged 59 to 91, for 17.5 years and found that women and men with the highest homocysteine levels were twice as likely, and four times as likely, respectively, to have a hip fracture than were women and men with the lowest levels.
Scientists from the University of California, San Francisco, studied 80 elderly women, average age 71, and found that women with the highest blood-fluid (serum) levels of vitamin B12 had significantly more hip bone mineral density (BMD) than women with the lowest levels.
In one of the first bone studies on children, reported in The Journal of Clinical Endocrinology & Metabolism, 120 Caucasian girls aged 8 to 14 volunteered to keep diet diaries. Girls whose daily diets had less than 220 mg of magnesium took 300 mg of elemental magnesium oxide per day, separately in two 150 mg capsules, or a placebo, for 12 months. Researchers measured bone mineral content (BMC) of the hip, thigh (femoral neck), and lower (lumbar) spine at the start and end of the study and found that compared to placebo, girls who took magnesium before, during, and in the late stages of puberty had significantly increased hip BMC without side effects.
Researchers from the University of Basel, Switzerland theorized that modern diets have fewer fruits and vegetables, and more dairy, grains, and meats, which may cause chronic, mildly elevated blood acidity and lower BMD. In this new 12-month study, post-menopausal women, average age 59, who took 1,173 mg of potassium citrate—a non-acidic (alkaline) form—per day had a one-percent increase in BMD of the lumbar spine, a result similar to pharmaceutical treatments, and lower blood acidity.
Reference: Journal of the American Society of Nephrology; 2006, Vol. 7, No. 11, 3213-22.
Improving diabetes
In a new study, diabetics who took Pycnogenol®, an antioxidant extract of French maritime pine bark, had significantly stronger small blood vessels (capillaries) compared to those who took a placebo. Researchers from the Gabrielle díAnnunzio University, in Chieti and Pescara, Italy, noted that all diabetics have weak capillary walls, a condition known as diabetic microangiopathy (DM). Damaged capillaries can leak blood and protein, slowing blood flow, and causing clotting and swelling (edema) in the limbs. In severe cases, those with DM may lose vision, and may develop leg ulcers that require amputation.
All 60 DM patients, aged 55 to 68, had used insulin for at least three years, and had no history of diabetic ulcerations. In the four-week trial, half the group took 150 mg of Pycnogenol, in three separate 50 mg capsules per day, while the other half took a placebo. The scientists measured blood flow, first while patients were lying down (prone), then while standing up, a transition that increases pressure, causing some capillaries to fail in those with DM.
Patients who had taken Pycnogenol showed a 34% increase in capillary blood flow while lying down, compared to a 4.7% increase in the placebo group, and a 68% improvement in capillary blood flow while standing, compared to an 8% improvement for placebo. Researchers also measured swelling at the ankle—to calculate capillary leakage, which occurs 10 minutes after standing up from a prone position—and found that those who had taken Pycnogenol were 17% less swollen, compared to 2.6% less swelling in the placebo group.
The doctors noted that the rapid strengthening of the capillaries was clinically remarkable, and concluded that Pycnogenol may prevent diabetic ulcerations, and can help control and treat DM.
Reference: Angiology; 2006, Vol. 57, No. 4, 431-6.
Healthier pregnancy
Women who took multivitamins before and during early pregnancy were less likely to have high blood pressure, swelling from excess lymph fluids, and kidney damage, together a set of pregnancy symptoms known as preeclampsia. Over the course of 15 years, researchers from the Department of Epidemiology at the University of Pittsburgh, Pennsylvania, enrolled 1,835 women—all of whom were less than 16 weeks pregnant at the time—in the Pregnancy Exposures and Preeclampsia Prevention Study. Researchers determined whether the women had used multivitamins or prenatal vitamins within the six months prior to enrolling in the study, and found that those who had taken vitamins were 45% less likely to have preeclampsia compared to those who had not taken vitamins.
The scientists adjusted for factors including race, ethnicity, income, marital status, the number of times a woman had given birth (parity), physical activity before pregnancy, and weight, and found that women who were overweight before pregnancy did not benefit from taking multivitamins. Researchers removed the overweight women from the statistics and found that non-overweight (lean) women who took vitamins were 71% less likely to develop preeclampsia than lean women who did not. The doctors reviewed the diets of the women, and found that those who ate fewer fruits and vegetables tended to be overweight, a finding that supported the conclusions of the study.
Preeclampsia occurs only in pregnancy and symptoms include blood pressure of at least 140/90, protein in the urine—which indicates kidney damage—and swelling in the feet, hands, and face, as excess lymph fluid builds up in the body. The doctors concluded that taking multivitamins before and at the time of conception (periconception) may help prevent preeclampsia, particularly in lean women.
Reference: American Journal of Epidemiology; 2006, Vol. 164, No. 5, 470-7.
Cinnamon helps absorb sugar
An extract of cinnamon reduced risk for diabetes in pre-diabetic volunteers, according to results from a new study. Researchers recruited 24 participants who had slightly raised blood sugar levels after not eating for 8 to 14 hours, a condition known as impaired fasting glucose, which is a risk factor for diabetes.
In the double-blind trial, doctors from the Joseph Fourier University, Grenoble, France, randomly assigned the recruits to take 500 mg of standardized cinnamon extract, in two 250 mg capsules per day, or a placebo, for 12 weeks. At the end of the study, scientists found that, compared to placebo, those who had taken cinnamon had less cell damage (oxidative stress) and higher blood-fluid (plasma) levels of antioxidants, factors which the doctors believe are related to the ability of the body to convert glucose into energy (insulin sensitivity). There were no changes in the placebo group. The researchers stated that this was the first study to test the antioxidant effects of cinnamon in humans.
In a related study in the July, 2006, issue of the European Journal of Clinical Investigation, researchers from the University of Hannover, Germany followed 79 type 2 diabetic patients who took 3 grams of standardized cinnamon extract capsules per day, or a placebo, for four months. At the end of the study, fasting plasma glucose levels dropped by an average of 10.3% for those who had taken cinnamon compared to a 3.4% drop in the placebo group. Doctors pointed out that those who had the highest fasting plasma glucose levels at the start of the study saw the largest drop in plasma glucose.
Reference: The 47th Annual American College of Nutrition Conference; October, 2006, Reno, Nevada, U.S.
Selenium and cancer
People with higher blood-fluid (serum) levels of selenium, the essential trace mineral, had significantly lower risk for bladder cancer, according to findings from a new Belgian study. Doctors conducted a case-control study that examined 178 persons with bladder cancer (cases) and 362 persons without bladder cancer (controls). The researchers took into account age, sex, smoking habits, and occupational hazards, and measured fruits and vegetables in the diet, as well as levels of vitamins A (retinol), C, and E, and total antioxidants in the blood.
After adjusting for these factors, scientists determined that those who had the highest levels of selenium—more than 96 mcg per liter of blood (mcg/l)—were 70% less likely to develop bladder cancer as were those who had the lowest levels of selenium; less than 82.4 mcg/l. Doctors also found that those in the middle group, whose selenium levels were between 82.4 mcg/l and 96 mcg/l, had 52% less risk of developing bladder cancer compared to those with the lowest levels. The researchers pointed out that, for each 10 mcg/l increase in the selenium level, the risk for bladder cancer dropped by 14%. The average person has about one liter of blood per 30 pounds of body weight.
According to the September, 2006, issue of Lancet Oncology, researchers first noticed the connection between selenium and cancer 40 years ago, when geographic studies reported lower death rates for cancer in regions of the U.S. with high levels of selenium. The first double-blind selenium-cancer study began in 1983 when researchers recruited 1,312 patients with histories of skin cancer at seven dermatology clinics located in low-selenium areas of the U.S. Doctors administered 200 mcg of selenium per day—about twice the average amount Americans consume—or a placebo, and followed up 10 years later. While results were not significant for skin cancer, there were 41% fewer total cancers, and 18% fewer deaths from cancer for selenium users compared to placebo.
Reference: International Journal of Urology; 2006, Vol. 13, No. 9, 1180-4.
Spice is very nice
Spices, including black pepper, chili peppers (capsaicin), ginger, green and black teas, and mixed spices can raise body temperature, burn calories, digest fats, and satisfy hunger (satiety), according to a review of clinical studies. Japanese men burned 23% more energy after a breakfast with capsaicin, and people who drank tomato juice with a little red chili pepper ate 10% fewer calories, compared to subjects that did not consume pepper. Black pepper and ginger activate receptors in the brain that increase body heat. These spices, plus coriander, cumin, onion, and turmeric, stimulate digestive enzymes and are heat-producing (thermogenic) ingredients that not only add flavor to foods, but provide health benefits, including lowering weight.
Reference: Physiology and Behavior; 2006, Vol. 89, No.1, 85-91.
Squeeze this!
Fruit juices that contain polyphenols may reduce risk for Alzheimer's Disease (AD), according to a new study. Researchers followed 1,836 dementia-free Japanese-American subjects from Seattle, Washington, average age 72, 54% of whom were women, for up to 10 years through 2001. Those who drank fruit juices three times per week or more were 76% less likely to develop signs of AD than were those who drank less than one serving per week. Researchers accounted for vitamins C, E, and beta-carotene in the diet. Subjects who carried a genetic marker (apolipoprotein E epsilon-4 allele) linked to late-onset AD-the most common form of the disease-appeared to have an enhanced effect from drinking juice. The researchers do not know what kind of juice the subjects drank, but are collecting blood-fluid (plasma) samples to try to find out, and suggest more studies in the meantime.
Reference: The American Journal of Medicine; 2006, Vol. 119, No. 9, 751-9.
Headache update
Many migraine sufferers are concerned about the toxic effects of prescription medications, and headache sufferers concerned about side effects resist taking daily over-the-counter drugs to treat symptoms. Doctors acknowledge the long-term risks of using and overusing these medications, and researchers are beginning to examine more natural treatments that may reduce frequency and prevent headache.
Butterbur (Petasites hybridus), a perennial shrub, in a 12-week trial using 100 mg per day of PetadolexÆ, a standardized butterbur extract, cut the number of migraines by more than half in 45% of those who took butterbur compared to 15% of those who took a placebo.
Feverfew (Tanacetum parthenium), a type of chrysanthemum, in a recent four-month multi-center study, reduced migraine attacks 46% more than placebo. The dosage was 6.25 mg three times per day of a special carbon-dioxide extract of feverfew leaf. Researchers believe that feverfew may help reduce migraine-induced nausea and light sensitivity.
Magnesium (trimagnesium dicitrate), in a 12-week double-blind trial using 600 mg per day, reduced the number of migraines by 41.6%, compared to a 15.8% reduction in the placebo group. Those in the magnesium group also had significantly fewer days with migraine, and took fewer drugs to treat symptoms.
Peppermint (Mentha piperita), in a double-blind study using an ethanol solution containing 10% peppermint oil, relieved headache pain as effectively as 1,000 mg of acetaminophen. In another study, 32 volunteers who applied peppermint oil to the temples reported significantly less headache pain.
Pycnogenol, a white pine bark extract, was part of a new three-month study where 12 patients who had not responded to conventional migraine treatments took 120 mg of pycnogenol, 60 mg of vitamin C, and 30 IU of vitamin E per day. Participants reported 41.4% fewer headache days at the end of the study, and headaches were also 27% less severe.
Riboflavin, in a three-month double-blind study using 400 mg per day, reduced the number of migraine attacks by at least half in 59% of those who took riboflavin compared to 15% of those who took a placebo.
Reference: Current Vascular Pharmacology; 2006, Vol. 4, No. 2, 117-28.
Diabetes update: new nerves, less pain
Acetyl-L-carnitine (ALC), a type of amino acid involved in healthy nerve function, alleviated pain, helped regenerate nerve fibers, and improved the ability to sense vibrations in diabetics suffering from a degenerative nerve condition known as diabetic neuropathy (DN). Researchers at Wayne State University, Detroit, Michigan, re-analyzed data from two 52-week double-blind clinical trials that included 1,257 DN patients who took either 500 mg or 1,000 mg of ALC per day.
Scientists found the number of nerve fibers in the area of the calf of the leg (sural nerve) had increased significantly, and that patients in both studies were better able to sense vibrations after taking ALC. Pain was the most bothersome symptom for 27% of patients at the beginning of the studies, and those who had taken the 1,000 mg dose of ALC reported significantly less pain. Doctors noted that those who had suffered from DN for the shortest amount of time reported the greatest pain relief.
DN can distort and interrupt nerve signals from the brain to the body, and researchers had originally designed these studies to measure the effects of ALC on the speed of nerve signals (conduction velocity), which decreases as nerve damage increases. When the results of the studies were not significant, the researchers decided to review the data for the effects of ALC on pain, and on its ability to generate new nerve fibers. ALC is widely used in Europe to treat pain in DN, and the university team is currently working with the U.S. Food and Drug Administration to approve ALC for pain in DN.
Reference: Diabetes Care; 2005, Vol. 28, 89-94.
Ginseng news for women
A new observational study from China found that women with breast cancer who took ginseng survived in greater numbers than women who did not take ginseng. The Shanghai Breast Cancer Study recruited 1,455 breast cancer patients from August, 1996 through March, 1998, and followed up through December, 2002. All of the women had chemotherapy, radiotherapy, or surgery. Researchers found that 398 women, or 27.4%, had used ginseng regularly before being diagnosed with cancer, and that number grew to 669 women-or 62.8% of the 1,065 survivors-over the average 4.8 years of follow-up.
Of the women who had used ginseng prior to diagnosis, 88.6% survived, compared to 80.0% of women who had not used ginseng prior to diagnosis. For the same two groups, 83.8% of prior users survived disease-free, compared to 77.4% of prior non-users. The researchers also found that women who started using ginseng after diagnosis reported improved quality-of-life, including measurements of physical, social, psychological, and material well-being. The scientists noted that quality-of-life measurements improved as the length of time the women used ginseng increased; and that for all users, the average dose was 1.3 grams of ginseng per day, which the women took for an average of 4.3 months per year.
The authors theorized, based on earlier test tube (in vitro) and animal studies, that ginsenosides-compounds in ginseng-appear to be responsible for the anti-cancer activity, and hope that these positive observations will encourage more double-blind, placebo controlled clinical trials to confirm the findings.
Reference: American Journal of Epidemiology; 2006, Vol. 163, No. 7, 645-53.
Less weight and fat
Chromium picolinate, an essential trace mineral, helped type 2 diabetics gain less weight and body fat, control blood sugar levels, and use (absorb) sugar (glucose), in a new study. For the first three months, researchers from the University of Vermont, Burlington, Division of Endocrinology and Metabolism, gave 37 type 2 diabetics a 5 mg dose of the antidiabetic drug glipizide per day plus a placebo substitute for chromium picolinate. The placebo was "single-blind," meaning the doctors knew-but the patients did not know-that it was a placebo. During the next six-month double-blind phase, 29 patients who continued took glipizide plus 1,000 mcg of chromium picolinate per day, or glipizide plus a placebo.
Doctors measured the percentage of fat, bone, and muscle (body composition), the ability to absorb glucose (insulin sensitivity), and blood sugar levels (glycemic control), at the start of the study, after three months, and at nine months. Those who took chromium gained 60% less weight, adding less than two pounds compared to almost five pounds for the placebo group. The chromium group increased the percentage of body fat by 0.12%, compared to 1.17% for placebo, a 90% improvement. For abdominal fat, the chromium group added less than five square inches, while the placebo group expanded by nearly 13 square inches, a 62% enhancement. Insulin sensitivity increased 80% more in the chromium group than in the placebo group.
The doctors concluded that chromium picolinate supplements improved insulin sensitivity and glycemic control while reducing weight gain and percentage increase in body fat in type 2 diabetics who were taking glipizide, compared to placebo. According to the U.S. National Institutes of Health, the intestinal tract absorbs only a small fraction of chromium, excreting the rest, and that vitamin C and niacin (vitamin B3) increase the ability of the body to absorb chromium.
Reference: Diabetes Care; 2006, Vol. 29, No. 8, 1826-32.
L-arginine for healthy hearts
In two new studies, the essential amino acid L-arginine allowed congestive heart failure (CHF) patients to exercise longer, lowered heart rates during and after exercise, and enabled the body to use oxygen more efficiently. In CHF, the heart cannot pump enough blood to the organs, causing patients to become short of breath and to tire easily. As blood flow from the heart slows, blood returning to the heart backs up, causing swelling in the legs and ankles. Fluid can also collect in the lungs, interfering with breathing. Researchers theorized that L-arginine would help relax and open (dilate) blood vessel walls that had become rigid and stiff-a condition known as endothelial dysfunction, a common and early risk factor in circulatory diseases-and allow more blood to flow through.
In the first crossover study, 21 patients with stable CHF took 9 grams of L-arginine per day for seven days, or a placebo, then switched treatment and placebo-the crossover phase-for another seven days. Researchers administered three exercise tests: before treatment, and after each treatment phase, and found that patients were able to exercise significantly longer after L-arginine than after placebo.
In the second study, researchers from the Institute de Physiologie, Strasbourg, France, tested the maximum exercise ability of each patient, then administered an identical 30-minute interval-endurance test before and after six weeks of treatment with L-arginine or placebo. In the L-arginine group, average heartbeats-per-minute decreased by 8.2 during exercise and by 6.7 during recovery. Researchers also found that the peak amount of salt-known as lactic acid or lactate-circulating in the fluid of the blood (plasma) declined by 24.2% in the L-arginine group. Lactate builds up during intense exercise and starves the body of oxygen (oxygen debt), causing fatigue and slowing recovery. There were no improvements in the placebo group.
Reference: International Journal of Sports Medicine; 2006, Vol. 27, No. 7, 567-72.
Go for it!
Creatine, a naturally occurring compound found in muscle tissue, combined with the herbs ginseng (panax ginseng, panax quinquefolius) and astragalus (astragalus membranaceus), helped older adults increase strength and fat-free (lean) muscle mass, lose body fat, and lower cholesterol in a 12-week strength-training program. The study included 44 adults aged 55 to 84, 21 males and 23 females, all non-smoking meat eaters in good health. The women had been post-menopausal for at least five years, and researchers asked all participants to maintain normal eating and other activities during the study.
Participants took 3,000 mg of creatine monohydrate, creatine plus 1,500 mg of a ginseng-astragalus extract (containing 10% ginsenosides and 1% flavonoids), or a placebo, in three divided doses at breakfast, lunch, and dinner. For three days each week, researchers supervised three upper-body and three lower-body exercises on weight-stack machines. Before and after the study, researchers tested maximum strength, and measured muscle, body fat, bone mineral content and density, blood levels of fat (triglycerides) and cholesterol, and administered a mood survey.
At the end of the study, all three groups had significant increases in strength and lean muscle mass, and significantly less body fat. Compared to placebo, the two supplement groups had significant increases in maximum strength in all exercises, with the exception of the bench press, where the creatine-only group was not significantly stronger than the placebo group. Researchers were surprised to find that the creatine-ginseng-astragalus group had 10% lower total cholesterol, 12% lower low-density lipoprotein (LDL, the "bad" cholesterol), and 18% lower triglycerides. Changes in cholesterol in the creatine-only and placebo groups were not significant. In addition, those in the creatine-ginseng-astragalus group reported feeling more energetic compared to reports from the creatine-only and placebo groups.
Reference: Journal of Sports Science and Medicine; 2006, Vol. 5, No. 1, 60-9.
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