Metionine is an essential amino that your body needs to produce creatine and facilitate normal metabolism and growth. Your body needs between 800 mg and 1,000 mg per day to maintain normal health, the University of Pittsburgh Medical Center says. As of 2011, there was no therapeutic dose for methione. Although generally considered safe, a study published in a 2007 issue of the “Journal of Nutritional Biochemistry” found that a diet high in methionine caused decreased body weight and decreased high-density lipoproteins in rodent test subjects.
Vegan Diets and Methionine
Eating foods low in methionine, such as those in a vegan diet of legumes, soy and nuts, together with adequate vitamin B-12 supplementation, helps to extend lifespan in rodent test subjects, according to a study published in a 2009 issue of “Medical Hypotheses.” Adhering to a vegan diet means carefully regulating bean and soy intake while including ample amounts of fruits. However, in order to maximize the benefits of a low methionine diet, adequate exercise is also required. More research is needed to further understand the long-term effects of a low methionine diet on humans.
Longer Life Span
Lifelong reduction of methionine dietary intake from 0.86 percent to 0.17 percent increased the life span of rat test subjects by 30 percent, according to a study published in a 1993 issue of “The Journal of Nutrition.” However, the study also found that a low methionine diet impaired growth despite increased food intake. Further research on the effects of a diet low in methionine on life span and growth will provide insight on its effects on humans
Foods to Avoid
Avoid foods like eggs, cheese, cod fish and seaweed, because they are high in methionine. Powdered egg whites contain about 3 g of methionine in every 100 g, the DietAndFitnessToday website notes. The methionine content of cheese, cod fish and seaweed is 1 g for every 100 g. Other dietary sources of methionine include high-protein foods like poultry, red meat and dairy products, the University of Pittsburgh Medical Center notes.
High-Density Lipoprotein and Homocysteine Levels
A study published in a 2007 issue of the “Journal of Nutritional Biochemistry” found that mice on a diet high in methionine lost more than 20 percent of their body weight, but also had lower high-density lipoprotein, or HDL, levels compared to mice on low methionine diets. The study fed the mice a low folate diet and supplemented with methionine or folate in their drinking water for about seven weeks. The results showed that fasting homocysteine levels were higher in mice fed a diet that was low folate but high in methionine compared to mice fed a high folate and high methionine diet. This suggests that folate is somehow able to offset the effects that methionine has on homocysteine levels. Homocysteine is an amino acid that has been associated with higher risk of conditions like heart attack and stroke. More research is necessary to determine how a low methionine diet affects HDL and homocysteine levels in humans.