Animal and in vitro studies suggest that olive oil phenols are effective antioxidants. The most abundant phenols in olive oil are the nonpolar oleuropein-and ligstroside-aglycones and the polar hydroxytyrosol and tyrosol. The aim of this study was to gain more insight into the metabolism of those phenols in humans. We measured their absorption in eight healthy ileostomy subjects. We also measured urinary excretion in the ileostomy subjects and in 12 volunteers with a colon. Subjects consumed three different supplements containing 100 mg of olive oil phenols on separate days in random order. Ileostomy subjects consumed a supplement with mainly nonpolar phenols, one with mainly polar phenols and one with the parent compound oleuropein-glycoside. Subjects with a colon consumed a supplement without phenols (placebo) instead of the supplement with oleuropein-glycoside. Ileostomy effluent and urine were collected for 24 h after supplement intake. Tyrosol and hydroxytyrosol concentrations were low (Ͻ 4 mol/100 mol of intake) in the ileostomy effluent, and no aglycones were detected. We estimated that the apparent absorption of phenols was at least 55-66% of the ingested dose. Absorption was confirmed by the excretion of tyrosol and hydroxytyrosol in urine. In ileostomy subjects, 12 mol/100 mol and in subjects with a colon, 6 mol/100 mol of the phenols from the nonpolar supplement were recovered in urine as tyrosol or hydroxytyrosol. In both subject groups, 5-6 mol/100 mol of the phenols was recovered from the polar supplement. When ileostomy subjects were given oleuropein-glycoside, 16 mol/100 mol was recovered in 24-h urine, mainly in the form of hydroxytyrosol. Thus, humans absorb a large part of ingested olive oil phenols and absorbed olive oil phenols are extensively modified in the body. J. Nutr. 132: 409 -417, 2002.
Background: Fat-soluble vitamin E and carotenoids are regarded as being protective against chronic diseases. Little is known about the effect of dietary fat on the bioavailability of these compounds. Objective: The objective of this study was to assess the effect of the amount of dietary fat on plasma concentrations of vitamin E and carotenoids after supplementation with these compounds. Design: During two 7-d periods, 4 groups of 14-15 volunteers received daily, with a low-fat hot meal, 1 of 4 different supplements: vitamin E (50 mg), ␣-plus -carotene (8 mg), lutein esters (8 mg lutein), or placebo. The supplements were provided in a low-or high-fat spread supplied in random sequence during either of the 2 experimental periods. Results: As anticipated, plasma concentrations of vitamin E, ␣-and -carotene, and lutein were significantly higher in the supplemented groups than in the placebo group. The amount of dietary fat consumed with the hot meal (3 or 36 g) did not affect the increases in plasma concentrations of vitamin E (20% increase with the lowfat spread and 23% increase with the high-fat spread) or ␣-and -carotene (315% and 139% with the low-fat spread and 226% and 108% with the high-fat spread). The plasma lutein response was higher when lutein esters were consumed with the high-fat spread (207% increase) than with the low-fat spread (88% increase). Conclusion: Optimal uptake of vitamin E and ␣-and -carotene requires a limited amount of fat whereas the amount of fat required for optimal intestinal uptake of lutein esters is higher.
Objective: To investigate the effect of black and green tea consumption, with and without milk, on the plasma antioxidant activity in humans. Design: In a complete cross-over design, 21 healthy volunteers (10 male, 11 female) received a single dose of black tea, green tea (2 g tea solids in 300 ml water) or water with or without milk. Blood samples were obtained at baseline and at several time points up to 2 h post-tea drinking. Plasma was analysed for total catechins and antioxidant activity, using the ferric reducing ability of plasma (FRAP) assay. Results: Consumption of black tea resulted in a signi®cant increase in plasma antioxidant activity reaching maximal levels at about 60 min. A larger increase was observed after consumption of green tea. As anticipated from the higher catechin concentration in green tea, the rise in plasma total catechins was signi®cantly higher after consumption of green tea when compared to black tea. Addition of milk to black or green tea did not affect the observed increases in plasma antioxidant activity. Conclusions: Consumption of a single dose of black or green tea induces a signi®cant rise in plasma antioxidant activity in vivo. Addition of milk to tea does not abolish this increase. Whether the observed increases in plasma antioxidant activity after a single dose of tea prevent in vivo oxidative damage remains to be established.
BackgroundIn addition to helping consumers make healthier food choices, front-of-pack nutrition labels could encourage companies to reformulate existing products and develop new ones with a healthier product composition. This is the largest study to date to investigate the effect of a nutrition logo on the development of healthier products by food manufacturers.MethodsA total of 47 food manufacturers joining the Choices Foundation in the Netherlands (response: 39.5%) indicated whether their Choices products were newly developed, reformulated or already complied with the Choices criteria and provided nutrient composition data for their products (n = 821; 23.5% of the available Choices products in August 2009).ResultsMost products carrying the logo as a result of reformulation and new product development were soups and snacks. Sodium reduction was the most common change found in processed meats, sandwiches, soups and sandwich fillings. Dietary fiber was significantly increased in most newly developed Choices product groups; for example, in fruit juices, processed meats, dairy products, sandwiches and soups. Saturated fatty acids (SAFA) and added sugar were significantly decreased both in reformulated and newly developed dairy products. Caloric content was significantly decreased only in reformulated dairy products, sandwich fillings and in some newly developed snacks.ConclusionsThe results indicate that the Choices logo has motivated food manufacturers to reformulate existing products and develop new products with a healthier product composition, especially where sodium and dietary fiber are concerned.
Background:A global push to reduce the amount of saturated and trans-fatty acids, added salt and sugar in processed food, and to enhance fruit, vegetable and whole grain intake, while limiting energy intake, exists for most populations.Objectives:To redesign the International Choices Program (note: this is unrelated to the US Smart Choices Program), initially Netherlands focused, by an international board of scientists to create a generic, global front-of-pack nutrition logo system that helps consumers make healthier food choices and stimulates product reformulation.Methods:The Programme is a product-group-specific-nutrient-profiling approach with a distinction between basic and discretionary foods. The basic product groups are main contributors of essential and beneficial nutrients, and are based on food-based dietary guidelines from more than 20 countries across the globe. Generic criteria are derived from international nutrient recommendations for trans-fatty acids, saturated fatty acids, sodium, added sugar, fibre and energy, and evaluated against food composition data from 12 countries across Europe and market reality (actual foods on the market). Selected debates such as the source of fibre are also presented.Results:Generic criteria and a decision framework were developed to further define food categories, so as to meet the unique country- and region-specific dietary needs. The result is a complete set of criteria that is evaluated on a regular basis to ensure its alignment with international dietary patterns, new scientific insights and current developments within the food market.Conclusions:These guidelines are currently used in a number of countries across the globe, and are being evaluated for effectiveness. Completed studies have demonstrated an increase in consumer awareness, a positive effect on product innovation and a potential impact on nutrient intakes.
The Nutrition Score is the first simple, transparent and straightforward method that can be applied globally and across all food and beverage categories to evaluate the nutritional composition. It can help food manufacturers to improve the nutritional value of their products. In addition, the Nutrition Score can be a starting point for a powerful health indicator front-of-pack. This can have a significant positive impact on public health, especially when implemented by all food manufacturers.
Phenols present in olive oil may contribute to the health effects of the Mediterranean lifestyle. Olive oil antioxidants increase the resistance of low-density lipoproteins (LDL) against oxidation in vitro, but human intervention studies have failed to demonstrate similar consistent effects. To better mimic the in vivo situation, plasma was incubated with either individual olive oil phenols or olive oil extracts with different phenolic compositions, and LDL was subsequently isolated and challenged for its resistance to oxidation. The results show that the ortho-dihydroxy phenols (hydroxytyrosol and oleuropein-aglycone) are more efficient than their mono-hydroxy counterparts (tyrosol and ligstroside-aglycone) in increasing the resistance of LDL to oxidation. However, the concentration of antioxidants required to inhibit LDL oxidation when added to whole plasma was substantially higher as compared to previous data where antioxidants are directly added to isolated LDL. In conclusion, this study supports the hypothesis that extra virgin olive oil phenols protect LDL in plasma against oxidation. The explanation that in vitro studies show protective effects in contrast to the lack of effect in the majority of human studies may be that the dose of the phenols and thus their plasma concentration in humans was too low to influence ex vivo LDL oxidizability. Further studies are required to gain a better understanding of the potential health benefits that extra virgin olive oil may provide.
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