It's all about essential amino acids

Life Extension Europe: collection of foods high in essential amino acids arranged in a circle on a grey rock background. Clockwise from left foreground: cheese slices on wooden board, three potatoes, small bowl with cottage cheese, three eggs, wooden board with red meat and chicken with parsley garnishing, small bowl with ivory navy beans, small jug of milk.

Protein helps build muscles and supports body functions. Our real need is for amino acids, the protein building blocks. 

The body breaks down proteins to obtain these amino acids, and it needs 20 specific amino acids to maintain good health.

Essential amino acids

The human body produces many amino acids. Yet, it is incapable of making nine of the amino acids you need. These are called the essential amino acids. You must get them from food in the diet, or through supplements.

High-quality proteins are those that contain all the essential amino acids. These amino acids are crucial for building and repairing muscle tissue. If we don't get enough essential amino acids, our body's ability to build and repair muscles will be compromised.

The 9 essential amino acids are

Conditional amino acids

Some amino acids become essential when you're unwell or stressed, such as:

One study showed that L-arginine and L-lysine seem to possess some properties able to influence bone fracture healing. The results of this study indicate that these amino acids accelerate and ameliorate the healing processes and positively contribute to good healing of bone fractures. (33)

Other protein amino acids

These are the other 11 protein amino acids

Alanine, arginine, asparagine, aspartic acid, cysteine, glutamic acid, glutamine, glycine, proline, serine, and tyrosine (plus: selenocysteine and pyrrolysine).

What foods contain amino acids?

Most animal-based proteins contain all essential amino acids.

Whey, seafood, and eggs are good examples. Many plant proteins lack one or more essential amino acids. But some plant proteins, including pea protein isolate and brown rice, stand out for their higher leucine content. 

And two or more plant proteins can be combined to make a protein-rich product with all essential amino acids. (1) Plant protein can also be fortified with the missing essential amino acids to make it a truly complete protein source. (2)

If you’re using an animal-based protein supplement such as whey or egg, look for one without a ton of other ingredients that you may not need.  

If you are lactose intolerant, choose whey protein isolate, which is 99% lactose free. Ideally, plant proteins should be blended, including two or more types of proteins, or they should have the missing essential amino acids added.

How much protein should I take?

From 1.0 to 1.2 g/kg body weight of protein daily.

The Recommended Dietary Allowance (RDA) of protein for adults 19 and older is 0.8 grams per kilogram of body weight (0.8 g/kg). However, it is now generally recommended that older adults consume from 1.0 to 1.2 g/kg body weight of protein daily. (3,4)

Protein intake should be evenly spaced throughout the day, in three or more meals. There’s a limit to the amount of protein a person can use at one time to build skeletal muscle. (5)

When we eat more protein and amino acids than we can use, we don’t store them for later use.  That is why we must consume protein in “doses” or regular meals throughout the day. 

High-quality proteins contain all essential amino acids, those the body cannot make and therefore must consume. 

All essential amino acids are needed for muscle protein synthesis. Fall short in one or more, and muscle protein synthesis will not be sustained at the same rate. (6)

Slowing the progression of sarcopenia

A higher protein intake has been shown in multiple studies to slow the progression of sarcopenia, improving quality of life. (10,11) Regular physical activity, including resistance exercise, is also vital for slowing muscle loss.

Protein powders make it easy to get more protein in the diet. It might, if it helps that individual reach the correct amount of dietary protein intake. Muscle mass gradually decreases with age, a process called sarcopenia. 

Sarcopenia develops around the fourth or fifth decade of life, (5) and can be worse due to chronic illness, inactivity, or inadequate protein and calorie intake. (6)

Once sarcopenia starts, a person loses 3% to 8% of muscle mass each decade (7) while strength decreases by 3% per year after age 60. (9)

Simple tasks like opening a container of food or lifting groceries can become difficult, and the risk of dangerous falls increases. (9)

Brain balancing through amino acids

Alongside the classical amino acids, there are more than 1000 non-protein amino acids! These have specific functions in biological systems, such as serving as signaling molecules, enzyme cofactors, or playing roles in the synthesis of various compounds.

In other words; they have wonderful benefits for your body, not to mention your brain. Some of the amino acids mentioned below are non-protein.


Nearly everyone feels naturally better once their serotonin levels are optimal. It has such a wide array of functions, involved with everything from sleep, to appetite, to impulse control to sexual desire.

It is the brain chemical that helps soothe us when we feel stressed or threatened, and it offers considerable protection to the brain against the damaging effects of cortisol. 

Because it is such a key brain chemical, there are considerable signs of serotonin depletion: 

  • Insomnia (or irregular circadian rhythms)
  • Craving sweets and other carbohydrates
  • Frequent muscle aches and pains
  • Impulsive behaviors
  • Moodiness
  • Particularly sadness
  • Anxiety
  • Irritability
  • Feeling emotionally sensitive or vulnerable
  • Feeling insecure
  • Lacking self-confidence
  • Low stress tolerance

Most people with anxiety, especially if their mood is low as well, may benefit by boosting their serotonin levels. Consider taking the following amino acid supplements: 


L-theanine is a non-protein amino acid found in high concentrations in green tea. Though you would have to consume an awful lot of tea to get a therapeutic dose of theanine. You can get more by taking a green tea extract, while you can also take a supplement containing L-theanine alone, or in combination with other calming agents.

Researchers have found that it can change brain waves, promoting a relaxed and alert state, associated with alpha waves. (12)

That makes it unusual because it can sharpen mental focus and calm anxiety at the same time. L-theanine is one of my most common treatments for anxiety and may help any of the seven types of anxiety. It is usually taken in doses from 50 to 200 mg once or twice daily. 

For severe anxiety, it may be taken three or four times per day. It is not habit-forming like so many anti-anxiety medications. There are no known drug interactions, though you should talk to your doctor before adding it to a medication. 


5-HTP can reduce anxiety and improve mood, and it can also help with sleep without causing sedation. If you're on an SSRI, it's best to consult your doctor before using it. (13)

An alternative is using tryptophan combined with its essential cofactors lysine and niacinamide instead of 5-HTP. Tryptophan is better able to remain stable in the blood and cross the blood-brain barrier, where it is converted to serotonin. If 5-HTP converts to serotonin in the blood, this serotonin will not cross the blood-brain barrier. 

Taurine may reduce brain shrinkage

The non-protein amino acid, taurine, facilitates a diverse range of biological functions. (14-18) Taurine has been shown to improve markers of health implicated in rapid-onset aging, (16,19-22) along with disorders such as heart disease, (14-18,15,16) sarcopenia (17), and dementia. (25)  

Taurine is an amino acid that increases glycine and GABA to calm the brain, and it also protects the brain by reducing the harmful effects of excess glutamate. (21)

Recent research challenges the belief that brain shrinkage is inevitable with age. Taurine, an overlooked amino acid, can boost brain health. As we age, taurine levels naturally decline, hindering new brain cell growth and contributing to brain disorders. 

However, taurine can reverse this decline, promoting new cell growth, restoring communication pathways between brain cells, and even activating dormant stem cells.

Replenishing it through energy drinks is not recommended, but you may calm your brain if you boost your taurine levels with safer methods.  

Taurine dosage

Taurine is usually taken in doses of 500 mg one to three times daily. It can cause slight drowsiness and if so may be taken at bedtime. 

It has also been known to reduce blood pressure, so you should use care if you are prone to hypotension or light-headedness. It may be taken with or without food.

Protein powder

Creatine: What is creatine?

Creatine is an organic compound made by combining three amino acids L-arginine, glycine, and L-methionine. It's known for its muscle-enhancing properties, catering to athletes and older adults alike. 

For athletes, it increases muscle power, reduces fatigue, and promotes muscle growth by boosting energy stores in muscles and the brain.  In older individuals, it benefits various muscle and nerve conditions like Parkinson's and muscular dystrophy, and may help with chronic fatigue and fibromyalgia.  

Combining creatine with whey protein, especially during resistance training, yields more significant gains in lean muscle and strength. Creatine helps combat age-related muscle loss (sarcopenia), especially when paired with resistance exercise, aiding older adults in preserving strength and independence.  

It can also boost growth hormone levels post-exercise, resembling youthful benefits. In short, creatine, a potent amino acid, offers muscle benefits for all ages, amplified when combined with whey protein and the amino acid glutamine. 

When people consume a diet with insufficient protein, their bodies will break down skeletal muscle to help meet amino acid needs for critical processes. 

Over time, this can take a toll. Low protein intake is associated with reduced muscle mass and decreased strength throughout life. (26,27)


Glutamine is the most abundant amino acid in the body, and is highly concentrated in the skeletal muscles that make movement possible. Maintaining healthy skeletal muscle is essential to overall good health and mobility. 

Important research shows that glutamine can help maintain healthy muscle mass in people who are susceptible to loss of lean body mass, such as those undergoing surgery. 

One study showed that supplementing individuals who had major surgery with glutamine prevented the decline in muscle glutamine levels and muscle protein synthesis that can occur following such a procedure. 

These findings strongly suggest that glutamine can prevent the loss of muscle tissue during recovery from surgery and have important implications for all those seeking to preserve lean muscle mass. (28) 

Whey protein

Whey protein, derived from milk, offers diverse health benefits. Whey protein is a powerhouse of essential amino acids, surpassing sources like soy. 

It's especially rich in branched-chain amino acids, vital for building and repairing tissues. It also contains sulfur-containing amino acids that boost the body's antioxidant defenses by turning into glutathione, a critical player in overall health, including immune support. 

It supports muscle health, strengthens immunity, and guards against heart disease and cancer. Its rapid absorption aids muscle preservation, especially with resistance training. 

Whey protein boosts glutathione, which is a vital antioxidant, aiding liver detoxification and overall well-being. It shows promise in preventing diseases in older adults, from cancer to cognitive function, making it a versatile protein source for all ages.


Three of the essential amino acids are called branched-chain amino acids (BCAAs)

  • The three BCAAs account for 35% of the essential amino acids in muscle proteins. (29)
  • BCAAs help with the maintenance and growth of skeletal muscle, 
  • and they serve as an energy source for muscle tissue during exercise. 
  • In one  study, BCAA supplementation was shown to reduce muscle-related soreness after exercise and accelerate muscle recovery. (30)
  • A meta-analysis of eight studies further supports this finding. (31)
  • Research suggests that to maintain healthy muscle tissue, aging adults often require more protein than younger adults.(32) 
  • Therefore supplementing with BCAAs offers a promising way to support healthy muscle maintenance and may reduce the risk of age-related muscle loss.

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