An essential nutrient for animals and people, selenium is a powerful antioxidant that plays a critical role in metabolism, reproductive health and the body’s natural defense system. The organic selenium used in the USP study was Sel-Plex, from Alltech, a natural source of selenium enriched yeasts with higher bioavailability than inorganic sources. According to the company, Sel-Plex is the only Food and Drug Administration-reviewed and the first EU-approved form of organic selenium for all animal species.
“We’re excited to share these independent results, obtained by one of the most prestigious universities in this field of study, with the global livestock and poultry sectors,” said Steve Elliott, global director of the mineral management program for Alltech. “Selenium has once again been confirmed as a critical component for the human diet, and Alltech is committed to delivering a safe and efficient source of selenium to animals and humans in a natural way.”
Studies like this are important to improve human nutrition in a time of great demand for healthier products, said Dr. Marcus Antonio Zanetti, lead researcher of the School of Animal Science and Food Engineering, USP. "Strengthening the immune system of people and helping health professionals, nutritionists and all those involved in the meat production chain find a practical way to do so is one of the objectives of this research," he added.
In the first part of the study, 48 Nellore bulls were divided into four groups with and without additional supplemental selenium, vitamin E and canola oil. The second phase aimed to provide selenium-enriched meat to a group of elderly people.
"We supplemented the diet of animals with 2.5 mg of organic selenium per cow per day for a period of three months during fattening and found that in addition to increasing the amount of selenium in the blood of animals, the mineral content in the meat produced was six times greater than meat from beef cattle that have not had the supplemented diet,” Zanetti said.
The cholesterol level in the blood and meat of the animals that were fed the selenium-enriched diet was also reduced significantly, he added.
In the second research phase, the researchers conducted a study in a nursing care facility in São Paulo to assess the effects of meat supplemented with selenium on lowering cholesterol in human blood. For periods of up to 90 days, the cattle meat supplemented with selenium and vitamin E was included in the meals of 80 elderly people in different variations on the menu. The special diet was coordinated by a registered dietician for the project.
A blood-test analysis for the group taken after 45 days showed an increase in the amount of selenium in the blood plasma. Results of cholesterol rates are not yet completed, Zanetti emphasized.
"However, through this research, we have seen an increase in the availability of vitamin E and selenium in the blood of the group that ate the meat,” Zanetti said.
Nutritionists say selenium is considered an important antioxidant mineral that prevents the formation of free radicals, enhances immunity and thus helps fight infections in humans. However, many people are still deficient in selenium in their daily diet. Selenium levels are low in the Brazilian diet due to the country’s mineral deficient soil, according to the faculty of pharmaceutical sciences, USP.
The development of supplemented products can help improve human nutrition, Zanetti believes. “The daily consumption of 200 grams [7 oz.] of meat supplemented with selenium is able to provide the recommended mineral [50 micrograms] daily intake,” he said.
In a previous trial, Zanetti and other researchers supplemented the diet of cows with sunflower oil, organic selenium and vitamin E to increase the mineral availability in milk produced by the animals. The diet supplemented with milk was offered to a group of children in first through fourth grade. The research results showed the additional improvement in the quality and preservation of enriched milk by increasing levels of selenium and vitamin E in the blood of the children.
“This is pioneering research on selenium enriched milk and meat that links animal feed and nutrition to human health. In the world, there has only been basic investigation into this, but nothing as extensive as our studies,” Zanetti concluded.