What’s Missing from Multi-Vitamin Supplements?January 2005
By Elizabeth Wagner, ND
Sesame Reduces Inflammation, Boosts Antioxidants
Sesamin, one of the lignans found in sesame seeds, has been reported to possess antioxidant effects and to scavenge reactive oxygen species.17 It apparently acts as an anti-inflammatory as well, reducing inflammation by increasing levels of dihomo-gamma linolenic acid, a precursor of anti-inflammatory prostaglandin E1. Sesame also decreases production of pro-inflammatory prostaglandin E2 and leukotriene B4 by inhibiting delta-5 desaturase enzyme activity.18 Studies in rats demonstrate that sesamin can lower serum lipids,19 while other animal studies suggest that sesamin may prevent hypertension.20
The tocopherols, the family of nutrients that includes vitamin E, are believed to play an important role in preventing some major diseases associated with aging, including heart disease and cancer. In humans, consumption of a moderate amount of sesame seeds has been found to significantly increase blood levels of gamma tocopherol,21 which appears to be an especially beneficial member of the vitamin E family. Animal studies likewise have demonstrated that intake of sesame seeds and sesame lignans, particularly sesamin, increases blood levels of gamma tocopherol.22 Sesame and its lignans appear to offer numerous benefits, including promoting healthy vitamin E levels, reducing inflammation, and promoting healthy blood lipids and blood pressure.
Health Benefits of Olive Extract
Health-conscious adults have long prized olive oil. As the principal source of fat in the Mediter-ranean diet, olive oil has been associated with a lower incidence of coronary heart disease and certain cancers. Extra-virgin olive oil contains abundant phenolic compounds such as hydroxytyrosol that are responsible for its strong flavor and high stability.23 Accu-mulating evidence indicates that the phenolic compounds in olives are powerful antioxidants (both in vitro and in vivo) and exert other potent biological actions that may be partly responsible for the health-promoting effects of the Mediterranean diet.23
One byproduct of the processing of olive oil is a water extract of olive that contains phenolic compounds that are strong scavengers of free radicals.24 The most potent of these appears to be hydroxytyrosol, which has also demonstrated antibacterial activity.24
In-vitro studies have demonstrated that olive polyphenols increase LDL’s resistance to oxidation.25 In a recent study examining whether this effect occurs in humans, subjects consumed virgin olive oil containing differing concentrations of phenolic compounds over the course of three weeks.10 Consumption of olive oil resulted in a decrease of in-vivo oxidized LDL, an increase in ex-vivo resistance of LDL to oxidation, and an increase in high-density lipoprotein (HDL).10 These effects were more pronounced in those who consumed olive oil with higher concentrations of polyphenols, suggesting that the polyphenols were responsible for the beneficial effects of preventing LDL oxidation and boosting HDL.10
A high intake of antioxidants is protective against the oxidative stress that is involved in the onset of several degenerative diseases. Animal studies suggest that olive polyphenols may protect against oxidative stress by sparing the consumption of vitamin E, a critical antioxidant, during normal physiological processes.26 Another study in animals found that hydroxytyrosol offered protection from the oxidative stress associated with inhaling sidestream smoke.27
Because dietary sources of olive oil may not provide enough of the potent polyphenols needed to obtain maximal antioxidant benefits,28 a potent supplemental dose rich in hydroxytyrosol is recommended.
Green Tea: Cancer Preventive and Cardioprotective
Tea consumption has been associated with reduced risk for numerous diseases, including cancer, coronary heart disease, stroke, and osteoporosis.29 Green tea is known for its antioxidant effects. Its main constituent is a polyphenol called epigallocatechin-3 gallate, or EGCG. Polyphenols may be responsible for green tea’s cancer-preventive effects. In-vitro studies show that green tea polyphenols potently induce apoptotic cell death and cell cycle arrest in tumor cells, but not in their normal cell counterparts.30 Various animal studies have shown that green tea inhibits tumor incidence and multiplicity in different organ sites such as the skin, lungs, liver, stomach, mammary glands, and colon.30 EGCG has been demonstrated to inhibit cyclooxy-genase-2 (COX-2) in human prostate carcinoma cells.31 Over-expression of COX-2 has been implicated in many pathological conditions, including cancer.31
Green tea extract helps protect the cardiovascular system. EGCG has been found to reduce LDL oxidation,32 which has been implicated in the formation of atherosclerotic plaques in the cardiovascular system. Green tea consumption has been associated with a lower incidence of coronary artery disease.33 A recent study demonstrated that regular consumption of green tea reduces the risk of developing hypertension,34 which accelerates atherogenesis and is associated with an increased risk of stroke.
Epidemiological studies suggest that green tea may play a role in preventing type II diabetes, while human studies have shown that green tea promotes healthy glucose metabolism.35 In diabetic mice, green tea lowered blood glucose levels,35 suggesting its promise in promoting healthy blood sugar levels.
Oxidative stress is known to play a pivotal role in the development of neurodegenerative diseases. Researchers are examining wheth-er green tea, with its potent poly-phenols, may protect the nervous system and alter brain aging. Ongoing epidemiological studies are investigating whether green tea may help to prevent progressive neurodegenerative disorders such as Parkinson’s disease and Alzheimer’s disease.36
Broccoli: Broad-Spectrum Cancer Protection
Broccoli is a rich source of disease-preventive compounds. D-glucarate from broccoli has been shown to be an effective phytonutrient against cancer, offering cancer protection by supporting healthy mechanisms of detoxification. Specifically, D-glucarate inhibits beta-glucuronidase, an enzyme found in certain gut bacteria.
One important mechanism by which the body eliminates toxic chemicals and hormones is by attaching glucuronic acid to them in the liver. Through the process of glucuronidation, the body removes carcinogenic substances such as nitrosamines, polycylic aromatic hydrocarbons, sex steroid hormones, and heterocylic amines. Beta-glucuronidase breaks the bond between these harmful metabolites and glucuronic acid, allowing toxins to be reabsorbed by the body. Elevated beta-glucuronidase activity has been correlated with increased risk for cancers, particularly hormone-dependent cancers such as breast, prostate, and colon cancers.37 By inhibiting beta-glucuronidase, D-glucarate supports the body’s excretion of toxins and hormones.
High intake of cruciferous vegetables has been associated with a reduced risk of cancer, particularly of the lung and gastrointestinal tract.8 This protective effect has been linked to the presence of glucosinolates,8 which are metabolized to compounds that have been shown to be powerful inducers of the liver’s Phase II detoxification enzymes.9 These liver enzymes are known to protect against chemical carcinogenes.9 Induction of Phase II enzymes also promotes the scavenging of free radicals and may relieve oxidative stress, thereby ameliorating hypertension and atherosclerotic changes.38
Numerous studies show that broccoli may contain more cancer-preventive nutrients than any other plant. In addition to containing D-glucarate, broccoli is rich in sulforaphane, a compound that has been found to block the formation of tumors initiated by chemical carcinogens and to induce cancer cell death.39 Sulforaphane and other broccoli compounds have been shown to prevent cancer by supporting the liver’s Phase II detoxifying enzyme systems.40 Broccoli sprouts contain 30-50 times more of these protective chemicals than are found in mature broccoli plants.41