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More than just proteins: the many roles of amino acids
Written byLaura Harcourt
Reviewed byHeeral Patel
There’s more to amino acids that meets the eye – they’re actually the building blocks of life…
Summary
1What are amino acids?
Amino acids are the molecules which make up proteins in your body...
2What do amino acids do?
Amino acids play a big part in many bodily functions from building proteins to providing energy and producing hormones...
3What foods are rich in amino acids?
The richest sources of amino acids include animal products like meat, but some plants are rich in amino acids too...
Your body can make over 100,000 different types of protein, vital large complex molecules which have so many roles in your body from building muscles to transporting molecules around the body.1 Each of these proteins are constructed from even smaller molecules called amino acids.2
These small, unassuming compounds actually play a massive role in shaping how we function. There are many kinds of amino acids, each with a special job, from keeping our hearts beating to helping our brains send messages.1,3
Here, we’ll delve into the world of amino acids, explore their diverse roles and how they contribute to the incredible way our body’s function.
What are amino acids?
Simply put, amino acids are small molecules which make proteins.4 The specific combination and sequence of amino acids is what determines the unique structure and function of each protein.3
There are 20 amino acids found in your body.5 Nine of these amino acids are known as essential amino acids, that means your body can’t produce them on its own and instead needs to absorb them through food. The remaining 11 amino acids are known as non-essential amino acids as your body produces them on its own.4
What do amino acids do?
Amino acids are vital for several roles within the body and contribute to so many essential functions. While each amino acid has its own specific role within your body, in general, amino acids are important for:6
- building proteins: the primary function of amino acids is to build proteins
- providing energy: amino acids can be broken down and used as an energy source when needed7
- producing neurotransmitters: some amino acids act as neurotransmitters, transmitting signals between nerve cells8
- producing hormones: amino acids are essential for the synthesis of various hormones, including insulin 9,10
- immune function: amino acids are crucial to produce antibodies and other immune cells 11
- transporting nutrients: some amino acids play a role in transporting nutrients throughout the body12
What are BCAAs?
You might have heard the term ‘branched-chain amino acids’ or BCAAs. This term refers to a group of three essential amino acids: leucine, isoleucine and valine.13,14
Their name ‘branched chain’ comes from their unique chemical structure.15 Each of these amino acids have a side chain with a branch, which distinguishes them from other amino acids.28
Foods rich in amino acids
A healthy, balanced diet is the best way to fuel your body with the amino acids it needs. From lean meats to vibrant vegetables, here are just some of the foods with amino acids:
- meat (beef, poultry, pork)16
- fish (tuna, cod, salmon)17,18
- eggs19
- dairy products (cheese, milk, yoghurt)20,21,22
- legumes (beans, lentils, chickpeas)23
- nuts and seeds (almonds, chia seeds, sunflower seeds)24
- soy products (tofu, tempeh, edamame)25
- whole grains (quinoa, brown rice, oats)26
- vegetables (broccoli, spinach, leafy greens)27
Animal-based foods like meat, fish, dairy and eggs are often considered the best sources of amino acids.28 This is because the amino acids in animal proteins are more easily absorbed and used by your body.45 They’re also complete proteins, meaning they contain all nine essential amino acids.45
Plant-based sources, like soy, can also be considered complete proteins.29 However, most plant sources are considered incomplete as they lack one or more essential amino acids.30
By combining different plant-based protein sources during the day, it’s thought that you can get enough essential amino acids. For example, eating beans and rice, lentils and quinoa or peanut butter and wholegrain bread.46
Amino acid supplements
Amino acid supplements, like BCAA powders or amino acid tablets, are becoming increasingly popular, particularly among athletes and fitness enthusiasts alike.27,31 You can often find amino acid supplements targeting specific types like arginine or lysine, as well as combined supplements which include multiple.
It’s worth bearing in mind that research into BCAA supplements is quite limited and we don’t know precisely how they interact with the body. There are some promising studies, but it’s always best to check with your doctor first before adding any new supplements into your diet. Read the product label carefully and be aware of any potential side effects.32,33
It’s also important to remember that balance is key. Your body needs all amino acids in the right amounts, too much of one can have negative effects so we recommend a diet first approach. If you struggle to get enough variety into your diet due to dietary restrictions or other reasons, then consider supplements.
Remember, a healthy and balanced diet is likely to be the best way to get all the nutrients you need to fuel your workouts.
The final say
Amino acids are the fundamental building blocks of life, playing critical roles in virtually every process in your body, from building muscles to regulating hormones and so much more. In fact, we have amino acids to thank for life as we know it.
A balanced, healthy diet that includes a variety of protein sources is the best way to make sure you’re getting enough of every amino acid in your diet – especially essential amino acids that your body can’t make on its own.
This article provides informational advice and is not a substitute for medical care. Curated by experts for accuracy, we take great care to ensure the information is up-to-date and relevant. However, you should always consult your GP or healthcare professional before using supplements or alternative products, particularly if you have medical conditions or are under supervision.
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