What You Need to Know About Essential Amino Acids and a Plant-Based Diet
Amino acids are called the building blocks of protein. Different combinations make different types of protein. As you’ll see, this is important, especially for vegans.
There are 20 different amino acids and two types, essential and nonessential. Your body can make nonessential amino acids, and you can get them by eating certain foods. Your body can not make essential amino acids, so you must get them from a food source.
If a protein has all the essential amino acids, it’s considered a complete protein source. Animal sources are complete sources, but most plant foods are not. Quinoa, soy, and chia seeds are the exceptions.

“Every four days, most of the lining of the gastrointestinal tract and the blood platelets are replaced. Most of the white cells are replaced in ten days. A person has the equivalent of new skin in twenty-four days and bone collagen in thirty years. All this continuous repair and work requires amino acids.”
The Healing Nutrients Within
The Essential Amino Acids Missing From Most Plant Foods Are Lysine, Tryptophan, Methionine, and Phenylalanine.
For vegetarians, there is a variety of food sources of amino acids. But for vegans, it is more of a challenge to get enough, especially of methionine.
Lysine
Your body depends on lysine for proper growth, to produce carnitine (a nutrient responsible for converting fatty acids into energy), and to help lower cholesterol. It also plays a significant role in the formation of collagen.
Collagen is a fibrous protein that makes up bones, cartilage, and other connective tissues, including the skin and tendons.
Best Sources of Lysine
- Cheese
- Eggs
- Cottage cheese
- Quinoa
- Spirulina,
- Soy products, (like tempeh and tofu), and
- Fenugreek seed.
Amino acids also play a role in maintaining a healthy metabolism, which is even more important as you age.
Phenylalanine
Your body converts the amino acid phenylalanine into the amino acid tyrosine. Tyrosine is needed to make thyroid hormones and the brain chemicals dopamine and norepinephrine.
If you’re deficient, symptoms could include confusion, low energy, depression, fuzzy thinking, memory problems, and a decreased appetite.
Best Food Sources
- Eggs
- Dairy products
- Some nuts and seeds
Tryptophan
Tryptophan plays a vital role in your mood. It makes serotonin, which is a neurotransmitter that makes you feel calm.
The supplement L-tryptophan is used to treat insomnia, stress, anxiety, depression, and migraines. It’s also utilized as a weight control aid because it releases a growth hormone that burns body fat.
Best Sources of Tryptophan
- Cheese (cottage, parmesan, and Swiss have the highest amount)
- Eggs
- Milk
- Nuts (especially almonds)
- Peanuts and peanut butter
- Soy
- Wheat germ
- Sesame seeds, and
- Pumpkin seeds
Methionine
Methionine is known as “the antidepressant.” Your body uses a combination of methionine and adenosine to produce SAM-e (S-adenosylmethionine). SAM-e relieves depression, elevates mood, and is a powerful antioxidant.
Methionine also helps your digestive system get rid of toxins and heavy metals from the liver and arteries.
Food Sources High in Methionine
- Avocado
- Ricotta cheese
- Wheat germ
- Whole milk
- Eggs
- Cheese
- Cottage cheese, and
- Oatmeal
Vegan Sources
If you’re a vegan or considering a vegan diet, you can get some methionine from wheat and rice.
Many newbie vegetarians and vegans are under the misconception that a protein is a protein. But, as you can see, the type of protein is key to maintaining good health. Understanding proteins can help you avoid getting your new diet derailed, especially if you are vegan.
Sources
Eric R. Braverman, M.D., The Healing Nutrients Within, (CA: Basic Health Publications, Inc. 2003)
University of Maryland Medical Center, Amino Acids Overview
Vegetarian & Vegan
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© 2021 Living Well Health Coach
Disclaimer: The information on this site is for information purposes only. It is not intended to replace your healthcare professional or provide diagnosis or treatment.