Men's Health, nutrition | June 5, 2017 | Author: Naturopath
Bodybuilders and marathoners have been using branch-chain amino acid supplements for decades. Here's what you need to know:
Amino acids are the smallest units that make up proteins in our bodies and in the foods we eat. There are three branch-chain amino acids (BCAAs): leucine, valine and isoleucine. Their molecular structures involve a side-chain of three hydrogen atoms and one carbon atom, creating a “branched chain”. Don't worry, that's the extent of the deep science in this article.
Like all amino acids, the body uses BCAAs to build proteins for muscles, cartilage, enzymes, hormones, and more. But BCAAs are particularly important for blood sugar regulation, energy production, and muscle health – up to a third of muscle protein is made of branch-chain amino acids. They account for 40% of the body's total amino acid reserve with around 20% of that found in the muscle.
Because of this huge protein reserve and demand from skeletal muscles, BCAAs have a fast-track delivery system from food to muscle. They jump the queue during digestion and are preferentially absorbed in the gastrointestinal tract and, unlike every other amino acid, BCAAs aren't degraded in the liver – once they have been absorbed in the gut, they are transported directly to the bloodstream and delivered to muscles.
Branch-chain amino acids are used in muscles as an energy source during exercise and to rebuild muscle proteins after exertion. The higher the concentration of BCAAs in the muscle, the better it functions and the bigger the muscle can become.
Boosting your BCAA intake can give you massive gains, but there are functional benefits to adding them to your workout shake too.
If you're getting into fitness for the first time, ramping up your training program, or looking to get 'swoll, then BCAA supplementation is the boost you need.
If exercise isn't your thing, eating a low-calorie diet can still lead to lose weight, but it can also send the body into a catabolic state where it breaks down muscles instead of fat. Evidence shows that supplementing with branch chain amino acids during a diet can help to maintain lean muscle mass while promoting fat loss . More muscle gives you a higher metabolic rate, so fast-track your weight loss by protecting your lean mass with BCAAs.
Leucine can also help to cut the cravings while you're on a diet. Studies have also shown that supplementation can reduce over-eating by improving feelings of satisfaction after meals . This is partially because of BCAAs' effects on blood sugar:
Athletes want steady blood sugar levels so that they can tolerate long training sessions, but supplementation can also be a powerful therapy for people with diabetes, obesity, stubborn weight-loss issues, and hormone imbalances. Research on isoleucine and valine has suggested that these branch-chain amino acids have a huge influence over blood sugar levels and insulin secretion . Leucine also appears to be involved, as people with type 2 diabetes excrete this BCAA at a faster rate than people with stable blood sugar levels .
Taking a BCAA supplement improves the release of hormones that control blood glucose from the brain, making it easier to stick to your diet and keep your blood sugar within healthy range  . Long-term supplementation has been shown to protect the proteins within the pancreas that produce and secrete insulin, as well as protect muscles from degeneration associated with type-2 diabetes. It can also improve insulin sensitivity, helping to get glucose into cells faster and quickly return blood sugar levels to normal .
As the body ages, we naturally lose muscle mass, balance, dexterity and strength. Branch-chain amino acids to the rescue! A 2016 study showed that taking a 6g dose of a BCAA supplement before exercise therapy resulted in significant improvement to over-all strength and balance in 3 months, as compared to taking a placebo before performing the same exercises .
A three-month trial recently tested the effects of leucine supplementation on the cognitive function of 38 frail elderly individuals. After three months of supplementation, the group's cognitive scores were improved by 30% .
Other studies have confirmed that supplementing with BCAAs in old age is safe, with an upper-limit of 35g per day – but as little as 6g can give significant results .
Daily requirements of branch-chain amino acids are estimated to be between 34mg – 144mg per kilogram of bodyweight, per day. The lower end of the scale was calculated by the World Health Organisation in 1984, so err towards the higher dosage range if you are looking for real results.
[your weight in kilograms] x 144 = [the milligrams of BCAAs you need per day].
Don't be afraid to go a little higher for therapeutic results – evidence shows that 15g – 35g per day is safe and effective for healthy individuals, and it appears to be safe to supplement BCAA at the same level throughout adulthood and into old age .
Because the branch-chain amino acids will be absorbed before any other amino acids, you can easily boost your BCAA levels by consuming whole foods.
Meat & fish: 3g per 84g serve
Tofu & Tempeh: 2.3g per 84g serve
Beans & lentils: 3g per cup
Dairy milk: 2g per cup
Eggs: 1.3g per large egg
Quinoa: 1 g per cup
Nuts: 1g per 28g
Source: FSANZ 
Given these levels, it's obvious that you may need to take a BCAA supplement to get the recommended 15g – 35g per day. Look for a supplement without any additives, preservative, artificial flavours, natural stimulants or compounds.
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