Nutrition

Am J Clin Nutr Supplement to January 2005 Symposium on Dietary Polyphenols and Health

Polyphenols: antioxidants and beyond1,2,3 Augustin Scalbert,  Ian T Johnson and  Mike Saltmarsh

“Research on the effects of dietary polyphenols on human health has developed considerably in the past 10 y. It strongly supports a role for polyphenols in the prevention of degenerative diseases, particularly cardiovascular diseases and cancers. The antioxidant properties of polyphenols have been widely studied, but it has become clear that the mechanisms of action of polyphenols go beyond the modulation of oxidative stress…. Polyphenols are the most abundant antioxidants in the diet. Their total dietary intake could b e as high as 1 g/d, which is much higher than that of all other classes of phytochemicals and known dietary antioxidants…Their main dietary sources are fruits and plant-derived beverages such as fruit juices, tea, coffee, and red wine.”

The history of ß-carotene and cancers: from observational to intervention studies. What lessons can be drawn for future research on polyphenols?1,2,3 Serge Hercberg

“For ß-carotene, we need to collect sufficient information from experimental, clinical, and epidemiologic research before we support any specific public health recommendations. The same principles must be applied to recommendations regarding polyphenols (in particular, which polyphenols, at which doses, to achieve which benefits for which populations).”

Inhibition of carcinogenesis by polyphenols: evidence from laboratory investigations Am. J. Clinical Nutrition,  Jan 2005;  81:  284S – 291S. Joshua D Lambert, Jungil Hong, Guang-yu Yang, Jie Liao, and Chung S Yang

“For example, compounds such as curcumin are effective when applied topically to the skin or administered orally to affect the colon but are not effective in internal organs such as the lungs.”

Cocoa antioxidants and cardiovascular health  Carl L Keen, Roberta R Holt, Patricia I Oteiza, César G Fraga, and Harold H SchmitzAm. J. Clinical Nutrition,  Jan 2005;  81:  298S – 303S.

“In the context of cardiovascular health, a particular group of flavonoids, namely, the flavan-3-ols (flavanols), has received attention. Flavanol-rich, plant-derived foods and beverages include wine, tea, and various fruits and berries, as well as cocoa and cocoa products. Numerous dietary intervention studies in humans and animals indicate that flavanol-rich foods and beverages might exert cardioprotective effects with respect to vascular function and platelet reactivity.”

Reversing the deleterious effects of aging on neuronal communication and behavior: beneficial properties of fruit polyphenolic compounds James A Joseph, Barbara Shukitt-Hale, and Gemma Casadesus Am. J. Clinical Nutrition,  Jan 2005;  81:  313S – 316S.

“… dietary supplementation with fruit or vegetable extracts high in antioxidants (eg, blueberry or spinach extracts) might decrease the enhanced vulnerability to oxidative stress that occurs in aging. These reductions might be expressed as improvements in motor and cognitive behavior. Additional research suggested that mechanisms in addition to antioxidant and antiinflammatory activities might be involved in the beneficial effects of these extracts; the most important of these might be their ability to increase cellular signaling and neuronal communication.”

 Polyphenols and disease risk in epidemiologic studiesAm. J. Clinical Nutrition,  Jan 2005;  81:  317S – 325S. Ilja CW Arts and Peter CH Hollman

“Plant polyphenols, a large group of natural antioxidants, are serious candidates in explanations of the protective effects of vegetables and fruits against cancer and cardiovascular diseases. Epidemiologic studies are useful for evaluation of the human health effects of long-term exposure to physiologic concentrations of polyphenols… The aim of this review is to summarize available epidemiologic data on the health effects of polyphenols… Data obtained to date suggest beneficial effects of both flavonoids and lignans on cardiovascular diseases but not on cancer, with the possible exception of lung cancer.”

Extract from Table 1

Reference	Followup Time years	Outcome	Relative Risk (less than 1 is better)
Geleijnse 2002	5.6	MI	0.35
Arts 2001	10	CAD	0.49
Hertog 1997	10	CAD	0.47
Hertog 1993	5	CAD	0.32
Keli 1996	15	Stroke	0.27
Knekt 2002	30	Lung cancer	0.64
Hirvonen 2001	6.1	Lung cancer	0.56
Goldbohm 1998	4.3	Lung cancer	0.99
Knekt 1997	24	Lung cancer	0.53

MI=Myocardial infarction; CAD=Coronary Artery Disease

Risks and safety of polyphenol consumption Am. J. Clinical Nutrition,  Jan 2005;  81:  326S – 329S.Louise I Mennen, Ron Walker, Catherine Bennetau-Pelissero, and Augustin Scalbert

“This article gives an overview of the potential hazards of polyphenol consumption… estrogenic activity…and… inhibits nonheme iron absorption and may lead to iron depletion” [note these are potential hazards of pills, but unlikely to be of concern with food sources]

Am JClin Nutr Jan, 2005
When to eat and how often?
Simply put, the question of whether there is a health benefit from the consumption of multiple small meals will ultimately depend on how much energy is consumed, as opposed to how often or how regularly one eats…First, is it easier to overeat under a regimen of frequent, irregular meals?..regular eating frequency was associated with lower reported ad libitum energy intakes and lower fasting total and LDL-cholesterol concentrations…Third, is the specific time of day that food is eaten important? With respect to this question, the potential for breakfast food consumption to reduce total daily intake (12) and the capacity for smaller evening meals to aid in weight loss (13) have both drawn renewed interest of late. ..the average underreporting [of eating amount] by the obese women may have been 22–27%”
Soy protein with or without isoflavones: in search of a cardioprotective mechanism of action1,2 http://www.ajcn.org/cgi/content/full/81/1/5
” Prevention of lipid oxidation and, specifically, LDL oxidation is thought to be potentially important for the prevention of atherosclerosis and ischemic heart disease (2)…In summary, the benefits of soy—if any—require further investigation to determine the mechanisms responsible for these effects. Until then, it remains prudent to recommend soy products in a heart healthy diet because of their nutritional value and as a healthy substitute for protein sources that are higher in saturated fat and cholesterol.”
Dietary fats, teas, dairy, and nuts: potential functional foods for weight control? http://www.ajcn.org/cgi/content/abstract/81/1/7
” Functional foods are similar to conventional foods in appearance, but they have benefits that extend beyond their basic nutritional properties…Some foods that might be classified as functional foods for weight control because of their effects on EE and appetite—including medium-chain triacylglycerols, diacylglycerols, tea, milk, and nuts—are reviewed here…dietary fats seem to be most promising and have been the most extensively studied for their effects on body weight control. However, the weight loss observed is small and should be considered mostly as a measure to prevent weight gain.”

a-Tocopherol disappearance is faster in cigarette smokers and is inversely related to their ascorbic acid status
” Conclusions: Cigarette smoking increased a-tocopherol disappearance. Greater rates of a-tocopherol disappearance in smokers appear to be related to increased oxidative stress accompanied by lower plasma ascorbic acid concentrations. Thus, smokers have an increased requirement for both a-tocopherol and ascorbic acid. “

Ingestion of a tea rich in catechins leads to a reduction in body fat and malondialdehyde-modified LDL in men http://www.ajcn.org/cgi/content/abstract/81/1/122
” Conclusion: Daily consumption of tea containing 690 mg catechins for 12 wk reduced body fat, which suggests that the ingestion of catechins might be useful in the prevention and improvement of lifestyle-related diseases, mainly obesity. ” pg 122-“The ingestion of tea extract or catechins induces antioxidant(8), antiviral (9), antiplaque-forming(10), and anticancer (11) activities, as well as decreases in blood pressure (12) and blood sugar (13).”
Growth of children at high risk of obesity during the first 6 y of life: implications for prevention http://www.ajcn.org/cgi/content/abstract/81/1/140
Objective: The objective was to assess differences in growth in the first 6 y of life in children born to either overweight or lean mothers. Conclusion: Anthropometric measures were not significantly different between groups at year 2; weight and lean body mass were greater at years 4 and 6, and fat mass was greater at year 6 in high-risk children [those who had overweight mothers]”

Calcium supplementation and bone mineral density in females from childhood to young adulthood: a randomized controlled trial
Objective: This study evaluated the long-term effects of calcium supplementation on bone accretion among females from childhood to young adulthood.
Design: A 4-y randomized clinical trial recruited 354 females in pubertal stage 2 and optionally was extended for an additional 3 y. The mean dietary calcium intake of the participants over 7 y was 830 mg/d; calcium-supplemented persons received an additional 670 mg/d.
Conclusions: Calcium supplementation significantly influenced bone accretion in young females during the pubertal growth spurt. By young adulthood, significant effects remained at metacarpals and at the forearm of tall persons, which indicated that the calcium requirement for growth is associated with skeletal size. These results may be important for both primary prevention of osteoporosis and prevention of bone fragility fractures during growth.

C&E News 12/20/04 – More fears about vitamin C proven wrong!
Some research 3 years ago suggested a mechanism by which vitamin C might cause harm. New research in PNAS shows that mechanism actually can prevent genetic damage by removing peroxidized lipids, and “may explain in part how the vitamin helps prevent diseases like cancer and heart disease.”

The Little Book of Willpower, supplement to Prevention Magazine
Setting goals – start with 1 or 2 mini-goals; realistic; be flexible
Work with body – take it slow, avoid pasta, salt, get fish, seeds, yoghurt; try grazing – smaller meals more often;
Eat mindfully – plan snacks sensibly; drink water; eat veggies except potatoes, corn, peas
Emotional eating – choose boredom foods wisely; keep a food journal; soothing foods
Planning meals – When you start cheating, be creative; don’t shop when you are hungry
Finding time – eat breakfast;
Eating and greeting – buddy up; drink water for every alcoholic drink
Having a drink – drink 8 glasses water? WRONG

J Nutrition Jan. 2005
Tocotrienols: Constitutional Effects in Aging and Disease
” Most notable are the interactions of tocotrienols with the mevalonate pathway leading to the lowering of cholesterol levels, the prevention of cell adhesion to endothelial cells, and the suppression of tumor cell growth. Furthermore, glutamate-induced neurotoxicity is suppressed in the presence of tocotrienols. This review summarizes the main antioxidant and nonantioxidant effects of tocotrienols and assesses their potential as health-maintaining compounds. “

Tea Catechins with a Galloyl Moiety Suppress Postprandial Hypertriacylglycerolemia by Delaying Lymphatic Transport of Dietary Fat in Rats
” Both tea catechins and heat-treated tea catechins suppressed postprandial hypertriacylglycerolemia [dangerous high fat level in blood – triacylglycerides]”

The Flavonoid Phloretin Suppresses Stimulated Expression of Endothelial Adhesion Molecules and Reduces Activation of Human Platelets
” Phloretin is a plant-derived phytochemical that is mainly present in apples. “

Directly Quantitated Dietary (n-3)[omega-3] Fatty Acid Intakes of Pregnant Canadian Women Are Lower than Current Dietary Recommendations
” During pregnancy, (n-3) PUFA are incorporated into fetal brain and retinal [eye] lipids. Docosahexaenoic acid [DHA, 22:6(n-3)], in particular, is required physiologically for optimal development and function of the central nervous system… Nutritional education of pregnant women to ensure adequate intakes of (n-3) PUFA for optimal health of mother and child and the inclusion of DHA in prenatal vitamins may be pertinent. ”
Subclinical Vitamin D Deficiency Is Increased in Adolescent Girls Who Wear Concealing Clothing http://www.nutrition.org/cgi/content/abstract/135/2/218
” We conclude that vitamin D deficiency is an important problem in Turkish adolescent girls, especially in those who follow a religious dress code; therefore, vitamin D supplementation appears to be necessary for adolescent girls. “

Symposium: Vitamin D Insufficiency: A Significant Risk Factor in Chronic Diseases
Overview of the Proceedings from Experimental Biology 2004 Symposium
” pressing need to define new dietary requirement for vitamin D… suggests a mean requirement of at least 500 IU (12.5 mg)…moves us away from a single renal source for [vitamin D…] to the concept of their being disease-preventing endocrine, paracrine, and autocrine uses of the active metabolite…involving cell proliferation and immunity “[pg 301-2] ” mild to moderate vitamin D deficiency may contribute to bone loss and muscle weakness”[pg332]

1. Nutr. 135:1-4, January 2005 – The Immunological Components of Human Milk and Their Effect on Immune Development in Infants, Catherine J. Field
   ” It could be suggested that milk is the communication vehicle between the maternal immune system and the infant, a system actively directing and educating the immune, metabolic, and microflora systems within the infant, while conferring multiple means of protection from pathogens…This update briefly reviews immune development in infants and focuses on current knowledge of how both the “classical” immune and the nonimmune ingredients found in mature human milk promote immune development, facilitate the development of tolerance, and regulate the inflammatory response of infants.” “Recently, a systematic review concluded that breast-feeding appears to protect infants from the development of atopic diseases (eczema and food and respiratory allergies), particularly if there is a family history (8). Other epidemiological studies have associated breast-feeding with reduced incidence of immune-mediated diseases, including celiac disease, inflammatory bowel disease, type 1 diabetes, rheumatoid arthritis, asthma, eczema, necrotizing enterocholitis, and multiple sclerosis [reviewed in (3,6)]. “

1. Nutr. 135:1-4, January 2005 – The Immunological Components ofHuman Milkand Their Effect on Immune Development in Infants, Catherine J. Field
   ” It could be suggested that milk is the communication vehicle between the maternal immune system and the infant, a system actively directing and educating the immune, metabolic, and microflora systems within the infant, while conferring multiple means of protection from pathogens…This update briefly reviews immune development in infants and focuses on current knowledge of how both the “classical” immune and the nonimmune ingredients found in mature human milk promote immune development, facilitate the development of tolerance, and regulate the inflammatory response of infants.” “Recently, a systematic review concluded that breast-feeding appears to protect infants from the development of atopic diseases (eczema and food and respiratory allergies), particularly if there is a family history (8). Other epidemiological studies have associated breast-feeding with reduced incidence of immune-mediated diseases, including celiac disease, inflammatory bowel disease, type 1 diabetes, rheumatoid arthritis, asthma, eczema, necrotizing enterocholitis, and multiple sclerosis [reviewed in (3,6)]. “