By Dr. Mark Atkinson, Medical Advisor to LiveHelfi
Last year, I worked with a client (let’s call her Emma) who came to me because she felt constantly tired. She described waking up unrefreshed, struggling to concentrate at work, and relying on caffeine just to get through the day. She wasn’t ill in any obvious way, but she knew something wasn’t right.
When we reviewed her nutrition, she was actually eating what many would call a “healthy diet”: plenty of vegetables, whole grains, and lean protein. On paper, she was hitting her calorie and protein targets. But in functional medicine, a root-cause approach to health optimisation, we don’t just look at the quantity of food. We also ask how the body is digesting, absorbing, and using those nutrients.
To get more clarity, I ran a comprehensive amino acid profile. The results were revealing. Emma’s overall protein intake looked fine, but the distribution of amino acids was out of balance. She was consistently low in certain key amino acids (lysine, tyrosine, and glycine), while others were more than adequate. This imbalance can happen for many reasons: limited variety of protein sources, digestive inefficiencies, or a mismatch between intake and individual needs.
Based on this, we made some targeted adjustments. Emma began rotating a wider variety of protein-rich foods into her diet, including sources she hadn’t been eating regularly. We also added a couple of specific amino acid supplements to fill the gaps identified in her profile. Alongside this, we worked on improving her digestion to help her body absorb what she was actually eating.
Over the next three months, Emma described feeling gradual changes. She noticed a steadier daily rhythm, reported more restful nights, and expressed that her overall sense of wellbeing felt different.
Why amino acids matter more than you think
Most people think of protein as this monolithic thing: you eat chicken, you get protein, end of story. But your body doesn’t see it that way. The moment protein hits your digestive system, it gets broken down into its component amino acids. Those amino acids then become the raw materials for practically everything your body needs to function.
Think of it this way. If your body were a construction site, amino acids would be the lumber, steel beams, and concrete. Without the right materials in the right amounts, the construction project (whether that’s building muscle, making molecules, or repairing tissue) doesn’t happen optimally.
I’ve been working with patients for over two decades, and I’m consistently struck by how often amino acid imbalances are overlooked as part of someone’s nutritional picture.
The essential versus non-essential story
Your body can produce certain amino acids on its own. These are called non-essential amino acids – though that name is a little confusing, since they are still part of many natural processes in the body. The amino acids that your body cannot produce, known as essential amino acids, must be obtained from your diet.
In nutrition science, there is also interest in situations where non-essential amino acids may receive more attention. Researchers have studied, for example, how lifestyle factors can influence the balance of amino acids.
Take glycine: although it belongs to the non-essential group, it naturally occurs in proteins such as collagen. Glycine is also a subject of scientific interest in areas related to nutrition and well-being.
Quality matters more than quantity
One of the biggest mistakes I see people make is focusing solely on hitting their protein numbers without paying attention to amino acid quality. You can eat 30 grams of protein from a highly processed protein bar and 30 grams from wild-caught salmon, but your body’s going to respond very differently.
Animal proteins (meat, fish, eggs, dairy) provide what we call complete proteins. They contain all the essential amino acids in ratios that closely match what your body needs. Plant proteins can be excellent too, but they often need to be combined strategically to cover all the bases.
I’m not advocating for any particular dietary approach here. I’ve worked successfully with vegetarians, carnivores, and everything in between. The key is understanding what you’re working with and making thoughtful adjustments based on your individual needs.
The functional medicine perspective
In nutrition science, amino acids are not only recognised as the building blocks of proteins but are also studied for their broader roles in metabolism. Researchers have shown particular interest in compounds such as tyrosine, tryptophan and theanine, each of which has been the subject of scientific exploration in different nutritional contexts.
How much protein?
General recommendations for adults are commonly cited at 0.8 g per kg body weight per day as a baseline. In sports and active-ageing literature, intakes around 1.2–1.6 g/kg/day are frequently discussed, depending on goals, dietary pattern and preferences. Individual needs vary; consider seeking personalised advice.
Regarding meal patterning, many practitioners prefer distributing protein across meals rather than concentrating most of it in one sitting.
Individual differences
There is growing interest in bio-individuality—the idea that people may respond differently to similar dietary patterns. Research frequently explores how lifestyle, environment and personal variation relate to nutrition. There is no single approach that works for everyone.
Putting it into practice
If you’re just starting to pay attention to amino acids, begin with food quality. Focus on getting complete proteins from sources you digest well. Pay attention to how different protein sources make you feel. Some people do better with fish and eggs, others with meat, still others with thoughtfully combined plant proteins.
Consider the timing of your protein intake. Instead of having most of your protein at dinner, try spreading it more evenly throughout the day.
If you’re curious about amino acids, the best place to start is by learning what each one does and then considering how it might fit your own goals, diet, and lifestyle. Individual amino acids can be useful tools, but they’re most effective when chosen thoughtfully, matched to what your body actually needs, rather than added on top of everything else. The more you understand how they work, the more confident you’ll feel in selecting the ones that make sense for you.
The bigger picture
Amino acids highlight that nutrition is not only about totals—it is also about the specific building blocks we choose each day. Informed choices about protein quality, meal patterning and, where appropriate, carefully selected supplements can help you make confident, well-considered decisions.
For those interested in diving deeper into amino acids and evidence-based supplementation strategies, I cover these topics extensively in Supplement Mastery Pro, including access to our intelligent protocol advisor that helps design personalised approaches based on individual needs and goals.
