Using data from the first National Health and Nutrition Examination Survey (NHANES I), scientists examined associations between nutrient intakes and skin appearance in 4,025 women between the ages of 40 and 74 years. Clinical examinations of the skin were conducted by dermatologists. Skin-aging appearance was defined as having a wrinkled appearance, dryness associated with aging (senile dryness), and skin atrophy (shriveling or shrinking).
Higher vitamin C intakes were associated with a lower likelihood of a wrinkled appearance. Higher linoleic acid (an omega-6 essential fatty acid) intakes were associated with a lower likelihood of senile dryness and skin atrophy. A higher than average fat and carbohydrate intake also increased the likelihood of a wrinkled appearance and skin atrophy. These associations were independent of age, race, education, sunlight exposure, income, menopausal status, body mass index, supplement use, physical activity, and energy intake.
Elevated intakes of vitamin C and linoleic acid and reduced intakes of fats and carbohydrates are associated with better skin-aging appearance. Promoting healthy dietary behaviors may have added benefit for the appearance of skin in addition to other beneficial health outcomes in the population.
A study published in the American Journal of Clinical Nutrition examined the relation between baseline plasma vitamin C concentrations and risk of incident stroke. The study included a British population of over 20,000 adult men and women. The participants completed a health questionnaire and attended a clinic during 1993–1997.
After an average follow-up time of 9.5 years, the participants in the top fourth of plasma vitamin C levels had a 42% lower risk of stroke compared to those with the lowest levels. These results were independent of age, sex, smoking, BMI, blood pressure, cholesterol, physical activity, diabetes, social class, alcohol consumption, and any supplement use.
Plasma vitamin C concentrations, therefore, may act as an indicator of lifestyle or other factors associated with reduced stroke risk and may be helpful in determining those at high risk of stroke.
A combination of prolonged exercise and fish oil can dramatically reduce levels of a fat that can cause hardening of the arteries, a leading cause of heart disease. Fat in the bloodstream is a primary contributor to atherosclerosis, or partial blockage of the arteries.
A study found that people who do prolonged, aerobic exercise have muscle cells that are able to quickly break down and reduce levels of a fat called triglycerides. Taking a fish oil supplement can reduce triglyceride levels even more.
The researchers studied triglyceride levels in recreationally active men after they’d eaten high-fat meals. One group ate a fatty meal after they exercised. A second group ate a high-fat meal after taking a four-gram fish oil supplement. A third group ate a high-fat meal after exercising and taking the fish oil supplement. A control group ate a high-fat meal only.
The study found a 38 percent decline in peak triglyceride levels in the men who took a fish oil supplement before they ate a high-fat meal. Peak triglyceride levels dropped 50 percent in the men who exercised and took a fish oil supplement before they ate a high-fat meal.
Regular exercise and fish oil supplements may be beneficial for people who are concerned about maintaining a healthy triglyceride level.
In a similar study, combining fish-oil supplements with regular exercise improved both body composition and heart disease risk factors. Overweight participants with various heart disease risk factors were assigned to one of three groups: Fish oil (approximately 1.9 grams/day of omega-3 fats), fish oil and exercise, or placebo (sunflower oil). The exercise group walked 3 days/week for 45 minutes. Heart disease risk factors and body composition were measured at 0, 6, and 12 weeks. The group taking fish oil had a significant reduction in triglycerides, increased HDL cholesterol, and improved arterial vasodilation (blood flow). Both fish oil and exercise independently reduced body fat.
This study showed that increasing intake of omega 3 fatty acids could be a useful addition to exercise programs aimed at improving body composition and decreasing cardiovascular disease risk.