Nutrition Diet: How do you get all 20 amino acids?

October 28, 2025 •

4 min read

The human body requires 20 different amino acids to function correctly. While the body can produce 11 of these itself, the remaining 9, known as essential amino acids, must be obtained from food. So, how do you get all 20 amino acids to support critical functions like tissue repair and hormone production?

Quick Summary

A varied diet is key to acquiring all 20 amino acids for vital bodily functions. Animal products and some plant foods offer complete proteins, while combining diverse plant-based options throughout the day effectively ensures a full amino acid profile.

Key Points

Essential Amino Acids: Your body cannot produce 9 of the 20 amino acids, so they must be obtained from your diet.
Complete Protein Sources: Animal products (meat, eggs, dairy) and some plants (soy, quinoa) contain all 9 essential amino acids.
Complementary Proteins: Combining different plant foods, like rice with beans, provides all essential amino acids over the course of a day.
Variety is Key: Eating a wide range of protein-rich foods, both complete and incomplete, is the best strategy for a full amino acid profile.
Beyond Muscle: Amino acids are crucial for many bodily functions, including hormone synthesis, tissue repair, and immune support.
Dietary Planning: Focus on incorporating varied protein sources into meals and snacks to easily meet your body's amino acid needs.
Supplements are Not Always Needed: Most people get sufficient amino acids from a balanced diet, and supplements should be discussed with a doctor.

What Are Amino Acids and Why Are They Important?

Amino acids are the fundamental building blocks of protein, essential for numerous bodily processes including building muscle, repairing tissues, and creating hormones and enzymes. Your body needs 20 standard amino acids to perform these functions. These are categorized as:

Essential Amino Acids: There are nine essential amino acids that your body cannot make; they must come from your diet. These include histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine.
Non-Essential Amino Acids: The body can produce 11 non-essential amino acids internally, such as alanine, asparagine, aspartic acid, and glycine.
Conditionally Essential Amino Acids: These are non-essential amino acids that become essential during specific conditions like stress or illness. Arginine, for example, is conditionally essential during recovery from serious injury.

The Difference Between Complete and Incomplete Proteins

Understanding protein sources is vital for obtaining all amino acids, particularly the essential ones. Dietary proteins are often classified as 'complete' or 'incomplete'.

Complete Proteins: These foods contain sufficient amounts of all nine essential amino acids. Excellent sources include animal products like meat, poultry, fish, eggs, and dairy. Some plant foods, such as soy, quinoa, and chia seeds, also provide complete protein.
Incomplete Proteins: Most plant proteins lack or are low in one or more essential amino acids. For instance, grains are often low in lysine, while legumes are low in methionine. However, combining different plant proteins throughout the day can provide all essential amino acids.

Strategies for Getting All Amino Acids on a Plant-Based Diet

For vegetarians and vegans, protein complementation is a strategy to ensure all essential amino acids are consumed. This involves combining different incomplete protein sources over the day to create a complete amino acid profile. Examples of complementary protein combinations include:

Grains and Legumes: Combining foods like rice and beans or hummus with whole wheat bread provides a full set of essential amino acids.
Legumes and Nuts/Seeds: Pairing lentils with walnuts or topping bean soup with seeds.
Legumes and Dairy (for lacto-vegetarians): A meal of lentils and yogurt.
Whole Grains and Nuts/Seeds: Enjoying peanut butter on whole-grain toast.

Comparing Animal and Plant Protein Sources


Feature	Animal Protein	Plant Protein	Notes
Completeness	Generally complete, providing all nine essential amino acids.	Mostly incomplete, but some sources (soy, quinoa) are complete.	Both can provide all essential amino acids through dietary variety.
Bioavailability	Typically high, meaning the body can easily absorb and use the amino acids.	Can be lower, but preparation methods like soaking and cooking can improve digestion.	Not a major concern with a varied diet and sufficient calorie intake.
Associated Nutrients	Often high in saturated fat and cholesterol, but also provides vitamin B12, iron, and zinc.	High in fiber, vitamins, minerals, and antioxidants, with no cholesterol.	Focus on lean animal proteins or varied plant sources for balanced nutrition.
Sustainability	Generally has a higher environmental footprint due to farming and resource use.	Tends to be more sustainable and environmentally friendly.	Growing area of focus for ethical and health-conscious consumers.

The Widespread Roles of Amino Acids

Amino acids are involved in numerous bodily processes beyond muscle building. These roles include:

Neurotransmitter Synthesis: Amino acids like tryptophan and phenylalanine are precursors to brain chemicals affecting mood and sleep.
Immune System Support: They are vital for immune cell function, and deficiency can impair the immune response.
Digestion and Metabolism: Amino acids aid food breakdown and metabolic regulation.
Tissue Repair and Wound Healing: They are essential for repairing damaged tissues.
Hormone Production: Amino acids are key components in the production of various hormones.

Ensuring Optimal Amino Acid Intake

Most healthy adults can easily meet their amino acid needs through a balanced diet. It's not necessary to combine specific plant proteins in a single meal; variety throughout the day is sufficient.

Include Protein in All Meals: Incorporate protein sources into each meal and snack.
Embrace Variety: Consume a mix of animal and plant proteins for a broad range of amino acids and nutrients.
Consider Activity Level: Increased physical activity may require higher protein intake.
Mindful Choices: Choose lean animal proteins and healthy cooking methods.
Consult a Professional: A registered dietitian can offer personalized advice for specific dietary needs.

Conclusion

Obtaining all 20 amino acids is crucial for a healthy body and is easily achievable with informed dietary choices. A varied diet that includes both animal and plant protein sources provides all the necessary building blocks for vital functions like muscle growth, hormone regulation, and overall health. For those on plant-based diets, combining different protein-rich plant foods throughout the day ensures a complete amino acid profile. Prioritizing variety and balance in your diet is the most effective way to guarantee your body receives the full spectrum of amino acids it requires.

Frequently Asked Questions

Essential amino acids cannot be produced by your body and must come from your diet, while non-essential amino acids can be synthesized by your body.

Most plant proteins are 'incomplete,' lacking one or more essential amino acids. However, some plant foods like soy, quinoa, and chia seeds are complete proteins and provide all nine essential amino acids.

No, the notion of needing to combine specific proteins at every meal is outdated. As long as you eat a variety of protein sources throughout the day, your body can synthesize the complete protein profile it needs.

Examples of plant-based complete proteins include soy products (tofu, tempeh, edamame), quinoa, chia seeds, and hemp seeds.

Yes, a well-planned and varied vegan diet can easily provide all the amino acids. Combining different plant proteins, like grains with legumes, is a simple and effective strategy.

For most people eating a balanced diet, supplements are not necessary to meet amino acid needs. They may be useful for athletes or individuals with certain health conditions, but consulting a healthcare provider is recommended.

Amino acids are the building blocks of protein, which is the main component of muscle tissue. Branched-chain amino acids (BCAAs) like leucine, isoleucine, and valine are particularly important for protein synthesis and muscle repair.