6 Nutrition Findings On Salmon, Dark Chocolate & More
6 Nutrition Findings On Salmon, Dark Chocolate & More
1) Nutrition and Training Before a Bodybuilding Contest
Scientists, coaches and athletes have argued about science and practice for at least 100 years. In 1904, coach Bill Reid from Harvard warned his football players not to become involved with the famous Harvard Fatigue Laboratory because they might hurt their performance. Scientists are often contemptuous of coaches because they don’t include the latest research findings in their game plans. In this tradition, Brazilian scientist Paulo Gentil urged bodybuilders to make pre-contest preparation consistent with the latest scientific research. He made several suggestions:
- Don’t use artificially sweetened beverages before a contest because they are associated with weight gain. Athletes should reduce sugar intake but avoid artificial sweeteners.
- Don’t exercise in a fasted state because bodybuilders won’t lose fat, and it will negatively affect caloric expenditure and fat metabolism.
- Avoid split routines before a contest and emphasize multi-joint exercises.
- Cut back on protein. Optimal protein intake for fat loss is 1.2 to 1.8 grams per kilogram of bodyweight. Most bodybuilders consume 2.4 grams per kilogram.
- Avoid extremely low-carbohydrate diets because they impair exercise performance.
- Avoid high-volume aerobics. Instead, bodybuilders should do high-intensity interval training.
Almost any program works if applied systematically and the athletes buy into it. Many of these ideas make sense, but none of these suggestions have been tested in elite bodybuilders. (Journal of the International Society of Sports Nutrition, 12: 50, 2015)
2) Whey Protein Inhibits Muscle Carnitine Accumulation
Carnitine is a chemical compound formed from the amino acids lysine and methionine. It is critical for transporting fatty acids from the cell interior into the mitochondria. Carnitine helps break down long-chain fatty acids and promotes oxygen consumption. The mitochondria are the powerhouses of the cells that provide the body’s energy needs, determine endurance exercise capacity and greatly influence life span. Carnitine is poorly absorbed into muscle cells. It is insulin-dependent. A study from the University of Nottingham in the U.K. found that muscle carnitine uptake was increased following consumption of a high-carbohydrate beverage, but decreased following ingestion of whey protein. Carnitine should not be taken at the same time as whey protein supplements. (American Journal Clinical Nutrition, 103: 276-282, 2016)
3) Which Is Healthier: Farm or Wild Salmon?
Salmon is a healthy food because it contains omega-3 fatty acids that protect against heart attack and stroke, promote infant brain development and help ease the symptoms of rheumatoid arthritis, Crohn’s disease, psoriasis and postpartum depression. A public health service group called the Environmental Working Group said that farm-raised salmon fillets sampled in three major cities contained unsafe levels of chemicals called PCBs that make their consumption dangerous— particularly in pregnant women. The PCB levels are above those recommended by the United States Environmental Protection Agency (EPA), but within those set by the U.S. Food and Drug Administration (FDA). Healthy fish choices high in omega-3s include wild salmon, sardines, herring and mackerel. Fish high in mercury, another dangerous contaminant, include albacore tuna, swordfish, shark, red snapper and halibut. In late 2015, the FDA approved genetically engineered farmed salmon and will not require specific source labels. (ConsumerLab.com, January 3, 2016)
4) Dark Chocolate Boosts Oxygen Consumption
Dark chocolate is high in flavonoids, which promote blood flow. Rishikesh Patel from Kingston University in the U.K., and co-workers, found that consuming 30 grams of dark chocolate per day for 14 days caused slight increases in maximal oxygen consumption, cycling efficiency and gas exchange threshold— the point at which expired carbon dioxide increases abruptly. These effects were small, and might not make much difference in performance. Many recent studies have touted the beneficial effects of flavonoids and polyphenol in food such as chocolate and red wine. They are somewhat effective in reducing inflammation and free radical damage to cells. They may have long-term health benefits, but probably have few meaningful acute effects on exercise performance. (Journal International Society Sports Nutrition, 12: 47, 2015)
5) Beetroot Juice Improves Blood Vessel Health
Foods high in nitrates, such as beetroot juice, stimulate the inner lining of blood vessels to secrete nitric oxide, a chemical that controls blood flow. Beetroot juice has positive effects on blood pressure, sexual performance and endurance exercise capacity. Beetroot juice has cardiovascular benefits in patients with high cholesterol— according to a six-week study led by Shanti Velmurugan from the William Harvey Research Institute in London, U.K. Subjects receiving beetroot juice showed a 24 percent improvement in blood vessel performance (flow-mediated dilatation). Beetroot juice also reduced platelet stickiness by 10 percent, which decreases the risk of blood clot formation and heart attack. Beetroot juice is a heart-healthy food that improves blood vessel health. (American Journal Clinical Nutrition, 103:25-38, 2016)
6) Dietary Guidelines Advise Healthy Eating Patterns to Prevent Disease
In January 2016, a joint report from the U.S. Department of Health and Human Services (HHS) and the U.S. Department of Agriculture (USDA) advised people to cut down on sugars and saturated fats, and limit sodium intake. The report included these dietary recommendations:
- Eat a variety of nutrient-dense foods, and pay attention to your food and beverage choices.
- Try to eat more healthy foods such as vegetables, fruits, grains, low-fat and fat-free dairy, lean meats and other high-protein foods.
- Eat more dark green and red and orange vegetables, beans and peas and other vegetables.
- Whole fruits should be high on your list.
- Restrict added sugar intake to less than 10 percent of calorie intake. These include syrup and high-sugar soft drinks, but do not include naturally occurring sugars found in milk and fruits.
- Less than 10 percent of calories should come from saturated fats.
The joint report recommends that you check food labels for information about calories, sugar and sodium. (U.S. Department of Health & Human Services, January 7, 2016)