FDA List of Dangerous Supplements
Illnesses and Injuries Associated With the Use of Selected Dietary Supplements.
This list of selected dietary supplements associated with serious safety problems is found in the section entitled “Illnesses and Injuries Associated With the Use of Selected Dietary Supplements” of an out-of-print 1993 FDA document “Unsubstantiated Claims and Documented Health Hazards in the Dietary Supplement Marketplace.”
Products marketed as “dietary supplements” include a diverse range of products, from traditional nutrients, such as vitamins or minerals, to such substances as high-potency free amino acids, botanicals, enzymes, animal extracts, and bioflavanoids that often have no scientifically recognized role in nutrition.
There is currently no systematic evaluation of the safety of products marketed as dietary supplements. Dietary supplements routinely enter the marketplace without undergoing a safety review by FDA. Published studies on the safety of these products are extremely sparse. There is no systematic collection and review of adverse reaction reports for dietary supplements, as there is for drugs, and physicians rarely seek information about their patients’ use of dietary supplements. Despite the lack of any system for gaining information about the risks of dietary supplements, an increased number of reports of adverse reactions to dietary supplement products has recently been recognized. Because of concern about these products, FDA has, in the last year, initiated an effort to collect and evaluate existing studies and case reports on safety problems associated with dietary supplements. As a result of that effort, FDA has begun to identify dietary supplements for which serious adverse reactions have been documented. A list of selected dietary supplements associated with serious safety problems follows. This list is not intended to include all hazardous ingredients in dietary supplements.
I. Herbals
Herbal and other botanical ingredients of dietary supplements include processed or unprocessed plant parts (bark, leaves, flowers, fruits, and stems), as well as extracts and essential oils. They are available in a variety of forms, including water infusions (teas), powders, tablets, capsules, and elixirs, and may be marketed as single substances or in combination with other materials, such as vitamins, minerals, amino acids, and non-nutrient ingredients. Although data on the availability, consumer use, and health effects of herbals are very limited, some herbal ingredients have been associated with serious adverse health effects.
A. Chaparral (Larrea tridentata)
Chaparral, commonly called the creosote bush, is a desert shrub with a long history of use as a traditional medicine by Native Americans. Chaparral is marketed as a tea, as well as in tablet, capsule, and concentrated extract form, and has been promoted as a natural antioxidant “blood purifier,” cancer cure, and acne treatment. At least six cases (five in the United States and one in Canada) of acute non-viral hepatitis (rapidly developing liver damage) have been associated with the consumption of chaparral as a dietary supplement. Additional cases have been reported and are under investigation. In the majority of the cases reported thus far, the injury to the liver resolves over time, after discontinuation of the product. In at least two patients, however, there is evidence that chaparral consumption caused irreversible liver damage. One patient suffered terminal liver failure requiring liver transplant.
Most of these cases are associated with the consumption of single ingredient chaparral capsules or tablets; however, a few of the more recent cases appear to be associated with consumption of multi-ingredient products (capsules, tablets or teas) that contain chaparral as one ingredient. Chemical analyses have identified no contaminants in the products associated with the cases of hepatitis. Products from at least four different distributors and from at least two different sources have been implicated thus far.
After FDA’s health warning, many distributors of chaparral products voluntarily removed the products from the market in December of 1992. Some chaparral products remain on the market, however, and other distributors who removed their products from the market are seeking to clarify the status of these products.
B. Comfrey (Symphytum officinale (common comfrey), S. asperum (prickly comfrey), S. X uplandicum (Russian comfrey))
Preparations of comfrey, a fast-growing leafy plant, are widely sold in the United States as teas, tablets, capsules, tinctures, medicinal poultices, and lotions. Since 1985, at least seven cases of hepatic veno-occlusive disease–obstruction of blood flow from the liver with potential scarring (cirrhosis)–including one death, have been associated with the use of commercially available oral comfrey products.
Comfrey, like a number of other plants (e.g., Senecio species), contains pyrrolizidine alkaloids. The toxicity of pyrrolizidine alkaloids to humans is well-documented. Hepatic veno-occlusive disease following ingestion of pyrrolizidine alkaloid-containing products, has been documented repeatedly throughout the world. Hepatic veno-occlusive disease is usually acute and may result in fatal liver failure. In less severe cases, liver disease may progress to a subacute form. Even after apparent recovery, chronic liver disease, including cirrhosis, has been noted. Individuals who ingest small amounts of pyrrolizidine alkaloids for a prolonged period may also be at risk for development of hepatic cirrhosis. The diagnosis of pyrrolizidine alkaloid-induced hepatic veno-occlusive disease is complex, and the condition is probably underdiagnosed.
The degree of injury caused by pyrrolizidine alkaloid-containing plants, like comfrey, is probably influenced by such factors as the age of the user, body mass, gender, and hepatic function, as well the total cumulative dose ingested and the type of exposure (i.e., whether exposure was to leaves or roots, infusions or capsules). Infants in general appear to be particularly susceptible to adverse effects of exposure to pyrrolizidine alkaloids; there are reports of infants developing hepatic veno-occlusive disease following acute exposure of less than one week. Transplacental pyrrolizidine poisoning has been suggested by the occurrence of hepatic disease in the newborn infant of a woman who consumed herbal tea during pregnancy.
Although liver damage is the major documented form of injury to humans from pyrrolizidine alkaloid-containing herbals, animal studies suggest that their toxicity is much broader. Animals exposed to pyrrolizidine alkaloids have developed a wide range of pulmonary, kidney and gastro-intestinal pathologies. Pyrrolizidine alkaloid-containing plants, including comfrey, have also been shown to cause cancer in laboratory animals.
Four countries (the United Kingdom, Australia, Canada, and Germany) have recently restricted the availability of products containing comfrey, and other countries permit use of comfrey only under a physician’s prescription.
C. Yohimbe (Pausinystalia yohimbe)
Yohimbe is a tree bark containing a variety of pharmacologically active chemicals. It is marketed in a number of products for body building and “enchanced male performance.” Serious adverse effects, including renal failure, seizures and death, have been reported to FDA with products containing yohimbe and are currently under investigation.
The major identified alkaloid in yohimbe is yohimbine, a chemical that causes vasodilation, thereby lowering blood pressure. Yohimbine is also a prescription drug in the United States. Side effects are well recognized and may include central nervous system stimulation that causes anxiety attacks. At high doses, yohimbine is a monoamine oxidase (MAO) inhibitor. MAO inhibitors can cause serious adverse effects when taken concomitantly with tyramine-containing foods (e.g., liver, cheeses, red wine) or with over-the-counter (OTC) products containing phenylpropanolamine, such as nasal decongestants and diet aids. Individuals taking yohimbe should be warned to rigorously avoid these foods and OTC products because of the increased likelihood of adverse effects.
Yohimbe should also be avoided by individuals with hypotension (low blood pressure), diabetes, and heart, liver or kidney disease. Symptoms of overdosage include weakness and nervous stimulation followed by paralysis, fatigue, stomach disorders, and ultimately death.
D. Lobelia (Lobelia inflata)
Lobelia, also known as Indian tobacco, contains pyridine-derived alkaloids, primarily lobeline. These alkaloids have pharmacological actions similar to, although less potent than, nicotine. There have been several reported cases of adverse reactions associated with consumption of dietary supplements containing lobelia.
Depending on the dose, lobeline can cause either autonomic nervous system stimulation or depression. At low doses, it produces bronchial dilation and increased respiratory rate. Higher doses result in respiratory depression, as well as sweating, rapid heart rate, hypotension, and even coma and death. As little as 50 milligrams of dried herb or a single milliliter of lobelia tincture has caused these reactions.
Because of its similarity to nicotine, lobelia may be dangerous to susceptible populations, including children, pregnant women, and individuals with cardiac disease. Lobelia is nevertheless found in dietary supplement products that are marketed for use by children and infants, pregnant women, and smokers.
E. Germander (Teucrium genus)
Germander is the common name for a group of plants that are contained in medicinal teas, elixirs and capsules or tablets, either singly or in combination with other herbs, and marketed for the treatment of obesity and to facilitate weight loss.
Since 1986, at least 27 cases of acute nonviral hepatitis (liver disease), including one death, have been associated with the use of commercially available germander products in France. These cases show a clear temporal relationship between ingestion of germander and onset of hepatitis, as well as the resolution of symptoms when the use of germander was stopped. In 12 cases, re-administration of germander was followed by prompt recurrence of hepatitis. Recovery occurred gradually in most cases, approximately two of six months after withdrawal of germander. Analyses of these cases does not indicate a strong relationship between the dosage or duration of ingestion and the occurrence of hepatitis.
Although the constituent in germander responsible for its hepatic toxicity has not been identified, germander contains several chemicals, including polyphenols, tannins, diterpenoids, and flavonoids.
On the basis of the 27 French hepatitis cases, the French Ministry of Health has forbidden the use of germander in drugs. Its use has been restricted in other countries.
F. Willow Bark (Salix species)
Willow bark has long been used for its analgesic (pain killing), antirheumatic, and antipyretic (fever-reducing) properties. Willow bark is widely promoted as an “aspirin-free” analgesic, including in dietary supplement products for children. Because it shares the same chemical properties and the same adverse effects as aspirin, this claim is highly misleading. The “aspirin-free” claim is particularly dangerous on products marketed, without warning labels, for use by children and other aspirin-sensitive individuals.
The pharmacologically active component in willow bark is “salicin,” a compound that is converted to salicylic acid by the body after ingestion. Both willow bark and aspirin are salicylates, a class of compounds that work by virtue of their salicylic acid content. Aspirin (acetylsalicylic acid) is also converted to salicylic acid after ingestion.
All salicylates share substantially the same side effects. The major adverse effects include irritation of the gastric mucosa (a particular hazard to individuals with ulcer disease), adverse effects when used during pregnancy (including stillbirth, bleeding, prolonged gestation and labor, and low-birth-weight infants), stroke, and adverse effects in children with fever and dehydration. Children with influenza or chickenpox should avoid salicylates because their use, even in small doses, is associated with development of Reye syndrome, which is characterized by severe, sometimes fatal, liver injury. Salicylate intoxication (headache, dizziness, ringing in ears, difficulty hearing, dimness of vision, confusion, lassitude, drowsiness, sweating, hyperventilation, nausea, vomiting, and central nervous system disturbances in severe cases) may occur as the result of over-medication, or kidney or liver insufficiency. Hypersensitivity, manifested by itching, broncho-spasm and localized swelling (which may be life-threatening), can occur with very small doses of salicylates, and may occur even in those without a prior history of sensitivity to salicylates. Approximately 5 percent of the population is hypersensitive to salicylates.
G. Jin Bu Huan
Jin Bu Huan is a Chinese herbal product whose label claims that it is good for “insomnia due to pain,” ulcer, “stomachic sic| neuralgia, pain in shrunken womb after childbirth, nervous insomnia, spasmodic cough, and etc.” Jin Bu Huan has been recently reported to be responsible for the poisoning of at least three young children (ages 13 months to 2 2 years), who accidentally ingested this product. The children were hospitalized with rapid-onset, life-threatening bradycardia (very low heart rate), and central nervous system and respiratory depression. One child required intubation (assisted breathing). All three utlimately recovered following intensive medical care.
Although the product label identified the plant source for Jin Bu Huan as Polygala chinensis, this appears to be incorrect since preliminary analyses indicate the presence of tetrahydropalmatine (THP), a chemical not found in Polygala. THP is found, however, in high concentrations in plants of certain Stephania species. In animals, exposure to THP results in sedation, analgesia, and neuromuscular blockade (paralysis). The symptoms of the three children are consistent with these effects.
An additional case of THP toxicity, reported in the Netherlands, appears to be associated with the same product, and is being investigated.
H. Herbal products containing Stephania and Magnolia species
A Chinese herbal preparation containing Stephania and Magnolia species that was sold as a weight-loss treatment in Belgium has been implicated recently as a cause of severe kidney injury in at least 48 women. These cases were only discovered by diligent investigations by physicians treating two young women who presented with similar cases of rapidly progressing kidney disease that required renal dialysis. Once it was determined that both these women had used the herbal diet treatment, further investigation of kidney dialysis centers in Belgium found a total of 48 individuals with kidney injury who had used the herbal product.
At the time that a report of these adverse effects was published in February 1993, 18 of the 48 women had terminal kidney failure that will require either kidney transplantation or life-long renal dialysis.
I. Ma huang
Ma huang is one of several names for herbal products containing members of the genus Ephedra. There are many common names for these evergreen plants, including squaw tea and Mormon tea. Serious adverse effects, including hypertension (elevated blood pressure), palpitation (rapid heart rate), neurophathy (nerve damage), myopathy (muscle injury), psychosis, stroke, and memory loss, have been reported to FDA with products containing Ma huang as ingredients and are currently under investigation.
The Ephedras have been shown to contain various chemical stimulants, including the alkaloids ephedrine, pseudoephedrine and norpseudoephedrine, as well as various tannins and related chemicals. The concentrations of these alkaloids depends upon the particular species of Ephedra used. Ephedrine and pseudoephedrine are amphetamine-like chemicals used in OTC and prescription drugs. Many of these stimulants have known serious side effects.
Ma huang is sold in products for weight control, as well as in products that boost energy levels. These products often contain other stimulants, such as caffeine, which may have synergistic effects and increase the potential for adverse effects.
II. Amino Acids
Amino acids are the individual constituent parts of proteins. Consumption of foods containing intact proteins ordinarily provides sufficient amounts of the nine amino acids needed for growth and development in children and for maintenance of health of adults. The safety of amino acids in this form is generally not a concern. When marketed as dietary supplements, amino acids are sold as single compounds, in combinations of two or more amino acids, as components of protein powders, as chelated single compounds, or in chelated mixtures. Amino acids are promoted for a variety of uses, including body-building. Some are promoted for claimed pharmacologic effects.
The Federation of American Societies for Experimental Biology (FASEB) recently conducted an exhaustive search of available data on amino acids and concluded that there was insufficient information to establish a safe intake level for any amino acids in dietary supplements, and that their safety should not be assumed. FASEB warned that consuming amino acids in dietary supplement form posed potential risks for several subgroups of the general population, including women of childbearing age (especially if pregnant or nursing), infants, children, adolescents, the elderly, individuals with inherited disorders of amino acid metabolism, and individuals with certain diseases.
At least two of the amino acids consumed in dietary supplements have also been associated with serious injuries in healthy adults.
A. L-tryptophan
L-tryptophan is associated with the most serious recent outbreak of illness and death known to be due to consumption of dietary supplements. In 1989, public health officials realized that an epidemic of eosinophilia-myalgia syndrome (EMS) was associated with the ingestion of L-tryptophan in a dietary supplement. EMS is a systemic connective tissue disease characterized by severe muscle pain, an increase in white blood cells, and certain skin and neuromuscular manifestations.
More than 1,500 cases of L-tryptophan-related EMS have been reported to the national Centers for Disease Control and Prevention. At least 38 patients are known to have died. The true incidence of L-tryptophan-related EMS is thought to be much higher. Some of the individuals suffering from L-tryptophan-related EMS have recovered, while other individuals’ illnesses have persisted or worsened over time.
Although initial epidemiologic studies suggested that the illnesses might be due to impurities in an L-tryptophan product from a single Japanese manufacturer, this hypothesis has not been verified, and additional evidence suggests that L-tryptophan itself may cause or contribute to development of EMS. Cases of EMS and related disorders have been found to be associated with ingestion of L-tryptophan from other batches or sources of L-tryptophan. These illnesses have also been associated with the use of L-5-hydroxytryptophan, a compound that is closely related to L-tryptophan, but is not produced using the manufacturing process that created the impurities in the particular Japanese product.
B. Phenylalanine
A number of illnesses, including those similar to the eosinophilia myalgia syndrome (EMS) associated with L-tryptophan consumption, have been reported to FDA in individuals using dietary supplements containing phenylalanine. There are also published reports of scleroderma/scleroderma-like illnesses, which have symptoms similar to EMS, occurring in children with poorly controlled blood phenylalanine levels, as well as in those with phenylketonuria (PKU), a genetic disorder characterized by the inability to metabolize phenylalanine.
III. Vitamins and Minerals
Vitamin and mineral dietary supplements have a long history of use at levels consistent with the Recommended Dietary Allowances (RDA’s) or at low multiples of the RDA’s, and are generally considered safe at these levels for the general population. Intakes above the RDA, however, vary widely in their potential for adverse effects. Certain vitamins and minerals that are safe when consumed at low levels are toxic at higher doses. The difference between a safe low dose and a toxic higher dose is quite large for some vitamins and minerals and quite small for others.
A. Vitamin A
Vitamin A is found in several forms in dietary supplements. Preformed vitamin A (vitamin A acetate and vitamin A palmitate) has well-recognized toxicity when consumed at levels of 25,000 International Units (IU) per day, or higher. (Beta-carotene does not have the potential for adverse effects that the other forms of vitamin A do, because high intakes of beta-carotene are converted to vitamin A in the body at much lower levels). The RDA for vitamin A is 1,000 retinol equivalents (RE) for men, which is equivalent to 3,300 IU of preformed vitamin A, and 80 percent of these amounts for women.
The adverse effects associated with consumption of vitamin A at 25,000+ IU include severe liver injury (including cirrhosis), bone and cartilage pathologies, elevated intracranial pressure, and birth defects in infants whose mothers consumed vitamin A during pregnancy. Groups especially vulnerable to vitamin A toxicity are children, pregnant women, and those with liver disease caused by a variety of factors, including alcohol, viral hepatitis, and severe protein-energy malnutrition.
There are some studies that suggest vitamin A toxicity has occurred at levels of ingestion below 25,000 IU. In addition, the severity of the injuries that occur at 25,000 IU suggests that substantial, but less severe and less readily recognized, injuries probably occur at somewhat lower intakes. Most experts recommend that vitamin A intake not exceed 10,000 IU for most adults or 8,000 IU for pregnant and nursing women.
B. Vitamin B6
Neurologic toxicity, including ataxia (alteration in balance) and sensory neuropathy (changes in sensations due to nerve injury), is associated with intake of vitamin B6 (pyridoxine) supplements at levels above 100 milligrams per day. As little as 50 milligrams per day has caused resumption of symptoms in an individual previously injured by higher intakes. The RDA for vitamin B6 is 2 milligrams. Vitamin B6 is marketed in capsules containing dosages in the 100-, 200-, and 500-milligrams range.
C. Niacin (nicotinic acid and nicotinamide)
Niacin taken in high doses is known to cause a wide range of adverse effects. The RDA for niacin is 20 milligrams. Niacin is marketed in dietary supplements at potencies of 250 mg, 400 mg, and 500 mg, in both immediate and slow-release formulations. Daily doses of 500 mg from slow-release formulations, and 750 mg of immediate-release niacin, have been associated with severe adverse reactions, including gastrointestinal distress (burning pain, nausea, vomiting, bloating, cramping, and diarrhea) and mild to severe liver damage. Less common, but more serious (in some cases life-threatening), reactions include liver injury, myopathy (muscle disease), maculopathy of the eyes (injury to the eyes resulting in decreased vision), coagulopathy (increased bleeding problems), cytopenia (decreases in cell types in the blood), hypotensive myocardial ischemia (heart injury caused by too low blood pressure), and metabolic acidosis (increases in the acidity of the blood and urine).
Niacin (nicotinic acid) is approved as a prescription drug to lower cholesterol. Many of the observed adverse reactions have occurred when patients have switched to OTC formulations of niacin, and particularly when they have switched from immediate-release formulations to dietary supplements containing slow-release niacin formulations without the knowledge of their physicians.
D. Selenium
Selenium is a mineral found in dietary supplement products. At high doses (approximately 800 to 1,000 micrograms per day), selenium can cause tissue damage, especially in tissues or organs that concentrate the element. The toxicity of selenium depends upon the chemical form of selenium in the ingested supplement and upon the selenium levels in the foods consumed. Human injuries have occurred following ingestion of high doses over a few weeks.
IV. Other Products Marked as Dietary Supplements
A. Germanium
Germanium is a nonessential element. Recently, germanium has been marketed in the form of inorganic germanium salts and novel organogermanium compounds, as a “dietary supplement.” These products are promoted for their claimed immunomodulatory effects or as “health-promoting” elixirs. Germanium supplements, when used chronically, have caused nephrotoxicity (kidney injury) and death. Since 1982, there have been 20 reported cases of acute renal failure, including two deaths, attributed to oral intakes of germanium elixirs. In surviving patients, kidney function has improved after discontinuation of germanium, but none of the patients have recovered normal kidney function.
One particular organogermanium compound, an azaspiran organogermanium, has been studied for its potential use as an anticancer drug. Forty percent of the patients in this study experienced transient neurotoxicity (nerve damage), and two patients developed pulmonary toxicity. Because of these side effects, medically supervised administration of this drug with monitoring for toxicity has been recommended for those using germanium chronically.
Grape Seed Extract Lowers Cholesterol
UC DAVIS STUDY SHOWS GRAPE SEED EXTRACT MAY BE EFFECTIVE IN REDUCING BLOOD PRESSURE Promising results prompt second human clinical study March 26, 2006 (SACRAMENTO, Calif.)
Miracle 2000 FAQ
Question: Is THIS Combination of Powerful Nutrients As Good As Taking Them Separately? Answer:
Taking nutrients in proper ratios is better than taking them separately. Sometimes taking minerals separately is not as beneficial because it can throw the body out of balance. For example, the proper ratio for taking calcium, which is best absorbed in the presence of magnesium, is 2 parts of calcium for each part of magnesium. Sodium and potassium also work best together and so do iron and copper. Each has an optimal ratio for best results. MIRACLE 2000
Meditation Grows More Grey Matter In The Brain
Research Shows Meditation is Associated with Increased Grey Matter in the Brain November 21, 2005 New Haven, Conn.– Meditation is known to alter resting brain patterns, suggesting long lasting brain changes, but a new study by researchers from Yale, Harvard, Massachusetts General Hospital, and the Massachusetts Institute of Technology shows meditation also is associated with increased cortical thickness.
The structural changes were found in areas of the brain that are important for sensory, cognitive and emotional processing, the researchers report in the November issue of NeuroReport. Although the study included only 20 participants, all with extensive training in Buddhist Insight meditation, the results are significant, said Jeremy Gray, assistant professor of psychology at Yale and co-author of the study led by Sara Lazar, assistant in psychology at Massachusetts General Hospital. “”What is most fascinating to me is the suggestion that meditation practice can change anyone’s grey matter,”" Gray said. “”The study participants were people with jobs and families. They just meditated on average 40 minutes each day, you don’t have to be a monk.”" Magnetic resonance imaging showed that regular practice of meditation is associated with increased thickness in a subset of cortical regions related to sensory, auditory, visual and internal perception, such as heart rate or breathing. The researchers also found that regular meditation practice may slow age-related thinning of the frontal cortex. “”Most of the regions identified in this study were found in the right hemisphere,”" the researchers said. “”The right hemisphere is essential for sustaining attention, which is a central practice of Insight meditation.”" They said other forms of yoga and meditation likely have a similar impact on cortical structure, although each tradition would be expected to have a slightly different pattern of cortical thickening based on the specific mental exercises involved. Co-authors include Catherine Kerr, Rachel Wasserman Jeffery Dusek, Herbert Benson and Metta McGarvey, Harvard; Douglas Greve, Brian Quinn, Bruce Fischl, Michael Treadway and Scott Rauch, Massachusetts General Hospital, and Christopher Moore, Massachusetts Institute of Technology. NeuroReport 16: 1893-1897 (November 28, 2005)
JAMA Call For More Studies on Low Carb Diets
More Evidence Needed for Low-carb Diets
9/4/2003
Researchers have expressed the need for long-term studies on the effects of low-carbohydrate diets. A review of this currently popular regime suggests that although successful, and with no obvious short-term adverse effects, it is not clear how the diet impacts people in middle age.
People who go on low-carbohydrate diets typically lose weight, but restricted caloric intake and longer diet duration are the biggest reasons why, according to the study from Stanford University Medical Center and collaborators at Yale University.
“”Low-carbohydrate diets have been extremely popular as of late, and the lay press has suggested they’re a safe and effective means of weight loss,”" said lead author Dr Dena Bravata, social science research associate at Stanford’s Center for Primary Care and Outcomes Research. “”While these diets are effective in the short term, weight loss results from reduced calories, not carbohydrate restriction.”"
The study appears in the 9 April issue of the Journal of the American Medical Association.
Despite the popularity of low-carbohydrate/ high-protein diets, and the concern of some in the medical community that these diets are too high in fat and can lead to kidney and liver problems and other health risks, Bravata said little evidence exists on the efficacy and safety of low-carbohydrate diets.
Bravata and her colleagues collected literature on low-carbohydrate diets published between 1966 and 2003. They reviewed a total of 107 diet studies, which involved 3,268 people from around the world. The studies were small and heterogeneous, with carbohydrate and caloric intake, diet duration and participant characteristics varying greatly.
However all of the studies had two things in common: none had participants with a mean age over 53 and none of the randomised and controlled studies lasted longer than 90 days.
“”Information on older adults and long-term results are scarce at best, and this should be kept in mind when looking at our findings,”" noted Bravata.
The researchers’ meta-analysis found that people on diets of 60 or fewer grams of carbohydrates a day (a threshold used in some of the popular low-carbohydrate diets) did lose weight. But the weight loss was associated with restriction of caloric intake and longer diet duration, not with reduced carbohydrate intake. It also found that the greatest weight loss occurred among those participants on diets with the highest baseline weight and lowest caloric content.
“”The greatest predictors of weight loss appear to be caloric intake and diet duration,”" she said. “”The findings suggest that if you want to lose weight, you should eat fewer calories and do so over a long time period.”"
The researchers found no significant adverse effects on cholesterol, glucose, insulin and blood-pressure levels among participants on the diets. But, Bravata stressed, the adverse effects may not have shown up within the short period of the studies. She also said losing weight typically leads to an improvement in some of these levels, so this could have had an impact on the numbers.
The researchers concluded that there is insufficient evidence overall to make recommendations for or against using the diets. Bravata said studies are now needed on the role of exercise in weight loss (as exercise information was excluded from this analysis), the long-term effects of these diets and the effectiveness and safety of these diets for people over the age of 53.
Co-author Christopher Gardner agreed that more studies on low-carbohydrate diets are needed. “”There wasn’t a lot of information from well-designed, randomised controlled trials…The obesity epidemic involves people having weight problems for years or decades, and we need long-term data on these diets’ effectiveness and safety.”"
Zinc Megadoses Linked to Health Problems
Zinc Megadoses Linked to Health Problems Media Misrepresents NIH Study Before you depose of your zinc supplements let us set the true facts out for you: ZINC IS NOT A CAUSE OF CANCER!
The Media has it entirely wrong once again in its unceasing effort to spread abysmal health half-truths by deliberately misrepresenting clinical studies. This week you may have heard that Zinc is linked to an increased risk of prostate cancer. By the way, when is the last time you saw a headline or a sound bite that Proscar is linked to prostate cancer? You didn’t, and in fact the only reports were that it prevented prostate cancer, right? If yo umiswed this read the facts at PROSCAR LINKED TO AGGRESSIVE PROSTATE CANCERS.
The NIH study that prompted these warnings actually contradicts the scare headlines. The fact is the national Institute of Health reported ONLY “”ingestion of 150 mg/day (over several years) has undesirable effects, such as immune system dysfunction and impaired antioxidant defense that are potentially related to prostate cancer.”"
Researchers at the National Cancer Institute used data from the Health Professionals Follow-Up Study (involving more than 50,000 men for over 14 years) to specifically examine 434 cases of advanced prostate cancer. They found that a “”chronic zinc oversupply”" may raise the risk of prostate cancer.
So if you look only at the superficial details, the news can be made to sound dire: compared to men who took no zinc supplements at all, men who took more than 100 mg per day for more than 10 years had almost THREE TIMES greater risk of prostate cancer.
And who takes more than 100 mg of zinc daily? Very few people, I would guess. Certainly no one who is paying attention to the widely-published warnings that zinc may be potentially toxic over a prolonged period at daily doses of more than 100 mg. At that level, research shows heart problems and anemia can occur.
But here’s the real clincher: the authors of the study stated that zinc intake from supplement doses of 100 mg per day or less was “”not associated with prostate cancer risk.”" Which is in complete contradiction to the headline: “”Zinc Supplements Increase Risk of Prostate Cancer”" (reported on Ivanhoe Newswire). Furthermore, the researchers stressed that other factors may have combined with the high zinc dosage to create the cancer risk.
All of a sudden, this dire warning doesn’t sound so dire.
Unless you go out of your way to add extra zinc to your vitamin regimen, chances are you’re not getting anywhere close to 100 mg. Most multivitamin supplements provide well under 50 mg of zinc. And you would need to eat dozens of oysters and a few servings of beef every day to even approach 100 mg of dietary zinc.
Meanwhile, the zinc that you are getting is very useful. In addition to enhancing the immune system, zinc helps repair damaged tissues, inhibits the abnormal clotting that contributes to cardiovascular disease, and is one of the key nutrients needed for DNA reproduction and repair. Zinc also helps keep your vision healthy.
So once again we see scare headlines doing a disservice to consumers who might easily be led to believe that taking any zinc at all is dangerous. Obviously, nothing could be further from the truth.
You Need Copper With Your Zinc
Final note for those of you who do include zinc in your daily supplement intake: it’s a good idea to add a little copper as well. Zinc can create a copper deficiency, and vice versa. Fortunately, SupplementSpot’s Complete Multi- Minerals has the copper you need plus the zinc and 16 other essential minerals.
Curcumin Blocks Colon Cancer
Curcumin Blocks Colorectal Cancer Hormone September 20, 2006 Curcumin has been found to block activity of a hormone implicated in the development of colorectal cancer
Green Tea Prevents, Combats Leukemia
Green Tea May Combat Leukaemia April 1, 2004 The active component in green tea, epigallocatechin-3-gallate (EGCG), already shown to fight several types of cancer, also appears to kill cells of the most common form of leukaemia, reports a US team this week.
The researchers found that EGCG interrupts the communication signals needed by cancer cells to survive, prompting them to die in eight of 10 patient samples tested in the laboratory.
The cells came from patients with B-cell chronic lymphocytic leukaemia (CLL), most often diagnosed in patients in their mid-to-late 60s and currently without cure. While chemotherapy is administered in the most severe cases, doctors have tended to stall use of this treatment in early stage patients, some of whom may live with it for decades and not require treatment. Green tea could however offer a less harmful, but effective alternative for this category of patients.
“”We’re continuing to look for therapeutic agents that are nontoxic to the patient but kill cancer cells, and this finding with EGCG is an excellent start,”" said Neil Kay from the Mayo Clinic. “”Understanding this mechanism and getting these positive early results gives us a lot to work with in terms of offering patients with this disease more effective, easily tolerated therapies earlier.”"
The findings are reported in an early electronic article in the journal Blood.
“”With these findings we may be able to pursue the idea of culling out early-stage patients who have historically not been treated and perhaps use an EGCG-based treatment. That’s our next step with our research,”" said author Yean K. Lee.
“”Our research goal is to identify new treatments for CLL that have a favourable side effect profile and can be used in patients with early stage disease to prevent progression. I think we’re getting there,”" added Mayo Clinic researcher Tait D. Shanafelt.
Since the 1970s, epidemiological studies of cancer have shown that in parts of the world where green tea is consumed, the incidence of solid tumour cancers such as breast, lung and gastrointestinal cancers is lower. Mouse-model testing of green tea’s cancer-prevention properties and lab tests on EGCG have confirmed that they protect against solid tumours and induce death in cancer cells from solid tumours.
The Mayo Clinic research suggests EGCG works by inhibiting a pathway in the leukaemia cells related to angiogenesis — the complex process that maintains nourishing blood flow to a biological structure, in this case a cancer cell.
Chronic lymphocytic leukaemia affects 2,750 new people in the UK every year and 165,000 in the USA and Canada. Over 200,000 are affected in Continental Europe.
Cherrys
New Evidence That Cherries May Help Prevent Gout
June18, 2003
A small study supports the reputed anti-gout efficacy of cherries, write researchers in the Journal of Nutrition this month.
The team found that the plasma urate dropped in 10 healthy women who ate sweet cherries after an overnight fast. Their urinary urate concentrations rose after they ate cherries, with peak excretion taking place three hours later.
As well as plasma urate markers, the researchers from the US Department of Agriculture’s ARS Western Human Nutrition Research Center at the University of California, Davis, also measured antioxidant and inflammatory markers in the study subjects. They found an increase in plasma ascorbic acid among the women, indicating that dehydroascorbic acid (the sole vitamin C content of the cherries) in fruits is bioavailable as vitamin C.
The women, aged 22
Flax Seed Supplementation Reduces Risk of Prostate Cancers
New Study Suggests Flaxseed And Low-Fat Diet Protective Against Prostate Cancer
DURHAM, N.C. — A low-fat diet supplemented with flaxseed may help reduce the risk of prostate cancer, researchers from Duke University Medical Center report in the July issue of Urology.
The researchers said dietary fat and fiber can affect hormone levels and may influence cancer progression. Flaxseed is high in fiber and is the richest source of plant-based, omega-3 fatty acids. Studies suggest that dietary fiber reduces cancer risk, and omega-3 fatty acids also have shown a protective benefit against cancer. Flaxseed is also a rich source of lignan, a specific family of fiber-related compounds that appear to play a key role in influencing both estrogen and androgen metabolism.
“”We thought flaxseed would be the perfect food for prostate cancer patients,”" said lead author Wendy Demark-Wahnefried, associate research professor in the department of surgery at Duke. “”It’s full of omega-3 fatty acids, fiber and lignan. Testosterone may be important in the progression of prostate cancer, and lignan in the flaxseed binds testosterone, so we thought the flaxseed might suppress the growth of prostate cancer cells. By pairing a low-fat diet with the flaxseed supplement, we also thought we could maximize the effect of the omega-3 fatty acids, since studies in animals show that the kind of fat we eat may be important for cancer progression.”"
The pilot study involved 25 patients with prostate cancer who were awaiting prostatectomy (surgical removal of the prostate). Baseline levels of prostate-specific antigen (PSA), testosterone, free androgen index and total serum cholesterol were determined at the beginning of the study. The tumors of those on the diet were then matched with 25 historic cases, equal in age, race, PSA level at diagnosis and biopsy Gleason sum (a scoring system used to grade prostate tumors) to compare tumor progression and biomarkers after the dietary intervention.
The men were on the low-fat, flaxseed-supplemented diet for an average of 34 days. Finely ground flaxseed was used in the study because, in its natural form, flaxseed is a pointy, tough seed that can puncture the intestines when consumed in the amounts used in this study (three rounded tablespoons a day). The ground flaxseed in the study was vacuum-packed (ground flaxseed can quickly go rancid) and had added emulsifiers for ease of mixing. The men were instructed to sprinkle the flaxseed on their cereal or mix it into juices, yogurt or applesauce. Researchers reported good compliance with the diet and said it was tolerated well.
At the end of the study, the researchers observed that the men on the diet had significant decreases in cholesterol, and both total and free testosterone. While there was a decrease in testosterone levels, they noted that none of the participants in the study suffered decreased libido or sexual dysfunction. There was a trend toward a decrease in PSA levels in men with early-stage prostate cancer (Gleason sums of six or less), but in men with advanced prostate cancer (Gleason sums of more than six) PSA levels continued to rise.
“”It’s not surprising that a diet therapy that was only taken for an average of 34 days had little effect on men with aggressive disease,”" Demark-Wahnefried said. “”But what we did see was that for the men on the diet, their tumor cells did not divide as quickly and there was a greater rate of apoptosis (tumor cell death) in this group.”"
With such a short-term dietary intervention, the researchers said they did not expect to see a difference in tumor biology between the diet-treated patients and the control patients, but were encouraged by the lower proliferation rates and significantly higher rates of apoptotic cell death. However, they said the results should be interpreted with caution, stressing that randomized controlled clinical trials are needed to confirm the results of the pilot study. Research on mice models is currently under way, and preliminary results support the findings in humans.
Demark-Wahnefried said it is still unknown if the low fat diet or the flaxseed — or a combination of the two — is the active component in the tumor reductions, adding more studies examining these elements independently are needed.