Will L-leucine powder cause internal heat?

Will L-Leucine Powder cause internal heat?

Many fitness bloggers claim, "L-leucine powder has no side effects; at most, it tastes bitter." However, real feedback reveals that internal heat is not uncommon; people simply don't attribute it to the leucine.

Digestive Discomfort

Diarrhea and Bloating: High concentrations of free leucine enter the small intestine, causing a sudden increase in osmotic pressure and a loss of water, leading to diarrhea. Consuming more than 10g of leucine at once on an empty stomach is most noticeable.

Acid Reflux and Belching: L-leucine powder stimulates gastric acid secretion, making relapse more likely in patients with gastroesophageal reflux or gastritis.

Nervous System Excitement

Insomnia and Palpitations: Leucine supplement activates the mTOR pathway, increasing the synthesis of sympathetic neurotransmitters. Sensitive individuals may experience insomnia or an increased heart rate.

Migraines
In some case reports, the leucine metabolite α-ketoisocaproic acid affects cerebral vascular tone, triggering headaches. If you experience "heatiness and insomnia" after taking BCAAs or pure leucine powder, you can:
① Split the total daily intake into smaller portions ≤5g;
② Avoid taking leucine two hours before bedtime;
③ Take it with carbohydrates to slow absorption.

Can pregnant women  and children take leucine?

Pregnant women and breastfeeding women

Animal studies have shown embryotoxicity: L-acetylleucine has been shown to cause fetal skeletal deformities and increased mortality in pregnant rats. While there is no equivalent evidence for regular leucine, human safety data is lacking.

Breastfeeding women: Leucine supplement enters breast milk and may disrupt the amino acid balance of newborns, so high-dose supplementation should be discontinued.

Children and adolescents: Use with caution during growth and development: Children have limited ability to metabolize branched-chain amino acids. Long-term high doses may disrupt the tryptophan-serotonin pathway, affecting sleep and mood.

An exception is for liver disease medication: Children with chronic liver disease and hepatic encephalopathy will receive a precise dose based on weight (compound leucine granules 3AA). Parents should never increase the dosage on their own. Postoperative or trauma patients
The double-edged sword of protein anabolic stimulant: Leucine does accelerate postoperative muscle synthesis, but high doses can increase insulin and blood ammonia levels, making it unsuitable for patients undergoing liver resection, kidney transplantation, or burns.
Clinical consensus
The American Society for Parenteral and Enteral Nutrition (ASPEN) recommends that postoperative patients consume no more than 2–3 g of leucine per day, and that this intake be monitored by a dietitian.

How to buy L-leucine powder?

If you wish to purchase large quantities of leucine raw materials, please contact the Sost Biotech raw material manufacturer.

Email:ericyang@xasost.com