|How to eat your way to last place.|
2) Does Soy Play a Role in the Lower Testosterone Levels of Vegetarians?
It very well may. A new case review published in the journal Nutrition presented the result of eating a soy-based vegan diet on testosterone levels and the related symptom of erectile dysfunction. A 19-year-old type 1 diabetic healthy male had been eating a vegan diet that included a large quantity of soy. He suffered loss of libido and erectile dysfunction, and had low testosterone levels. The subject stopped the vegan diet and within one year, his testosterone levels were normal and sexual function was regained.
Researchers suggest that high isoflavonoid intake resulted in disregulation of sex hormones and low testosterone levels in this male, which provides insight into the relationship between vegetarian diets that typically contain soy, and low testosterone.
|God I could really use some soy right now.|
3) What are other Possible Reasons for Lower Testosterone Levels in Vegetarians?
Vegetarian athletes are at increased risk for deficiencies in these areas because strength training and sports performance can significantly deplete some of these nutrients. Vegetarians do tend to have higher levels of vitamin C, E, beta carotene, and omega-6 fatty acids. Be aware that in addition to health issues from low zinc, vitamin D, calcium, and iron, vegetarians who have an imbalance of omega-6 to omega-3 fatty acids can be at risk for cardiovascular complications and an imbalance of anabolic and catabolic hormone levels. Ideally, you want a fairly even ratio of omega-6 to omega-3 fatty acids in the diet.
Omega-3s Fatty Acids
Optimal intake of omega-3s is related to healthy testosterone levels. For example, a new study performed on boars found that giving them an omega-3 supplement resulted in higher testosterone than those fed animal fat. Researchers concluded that omega-3s can improve fertility and anabolic hormone production in these animals, evidence that does have positive implications for humans.
Low iron is probably one of the best known deficiencies of vegetarian and vegan diets and it can lead to poor health and low energy levels. Iron is an essential nutrient because it is a central part of hemoglobin and oxygen exchange in the blood. Iron and testosterone levels in men appear to be closely related. In a study of diabetic men with low testosterone, 24 percent had anemia, which is linked to reduced iron availability in the body. Lower testosterone levels were found to be independently associated with lower hemoglobin and iron levels. Be aware that low testosterone and low iron are also related to development of chronic kidney disease and chronic inflammation.
A second study provides support that low testosterone and low iron are interrelated. Data from participants with low testosterone, all of whom had chronic kidney disease, were 5.3 times more likely to be anemic than those with sufficient testosterone levels. Researchers have not clarified the biological mechanisms relating testosterone and iron, but it is clear that low levels are detrimental to male health.
|Iron: Lift it, Eat it, Become it|
Zinc is a critical hormone for robust testosterone levels, and vegetarian diets can lead to low zinc intake. For example, in a study of 88 men aged 40 to 60 years, those with normal testosterone levels had a significantly higher zinc level compared to those with low testosterone levels. Low zinc levels were directly correlated with low testosterone levels, and this has been suggested as a factor in male menopause.
A second study found that zinc supplementation for four weeks led to higher testosterone levels after exhaustive high-intensity exercise than taking either a placebo or a selenium supplement. Researchers note that zinc enhances various mechanisms including elevating the conversion rate of androstenedione to testosterone, and that paired with high-intensity exercise, the body produces testosterone at an even higher rate.
Be aware that zinc is one of the most common mineral deficiencies and being vegetarian puts you at greater risk because many foods with the highest zinc content are animal derived such as oysters, veal liver, beef, and lamb. Zinc can be gotten from non-meat foods and seeds—sesame, pumpkin and watermelon seeds are particularly high in zinc.
The American population has been shown to be chronically deficient in vitamin D, and this mineral is critical for many biological processes including the production of testosterone. Vitamin D is produced in the body after sun exposure and can be consumed in the diet, but the best food sources of vitamin D are meat and fish products, meaning that vegetarians are at greater risk for vitamin D deficiency.
A new study on the relationship between testosterone and vitamin D found that taking a vitamin D supplement raised testosterone levels in previously deficient men, aged 20-49. Supplementing with 3,332 IUs of vitamin D daily for one year resulted in significant increases in total, free, and bioactive testosterone. There was no change in testosterone levels in a placebo group. Be aware that optimal vitamin D is crucial for muscle strength, power, and force development, possibly because of its relationship with testosterone production!
4) Are there Other Nutritional Negatives to A Vegetarian Diet For an Athlete?
Meat and fish are the best sources of creatine, with large amounts being found in beef, salmon and tuna. Of course, you can take a creatine supplement, if you’re a vegetarian, but with all this evidence, it might be easier to simply eat meat. Be aware that when choosing meat, opt for organic, local, and free range as much as possible. The hormones and antibiotics in nonorganic meat will mess with your hormones and likely negate a lot of the valuable data presented here.
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