Facts
Why lysine is good for you
Lysine is an essential amino acid and is required for growth and bone development in children, assists in calcium absorption and assists in maintaining the correct nitrogen balance in the body, as well as maintaining lean body mass.
Lysine is also needed to produce antibodies, hormones, enzymes, collagen formation as well as repair of tissue.
Important lysine facts
- Since lysine assists with building muscle protein, it is useful for patients recovering from injuries and recovery after operations
- Foods with a higher lysine to arginine ratio is required for preventing cold sores – animal proteins have a 3/4:1 ratio, while plant proteins have a 1:1 ratio
- Of all the amino acids, lysine is the most sensitive to the effects of food processing, such as dry heat. The amount of protein available in legumes and other sources of lysine can be significantly reduced if they have been toasted or roasted
Lysine works best with
Health
Lysine and health
- Cold sores and herpes – most studies show that lysine is useful in preventing or treating cold sore (herpes simplex 1) once they have erupted. Lysine has not been proven to treat genital herpes as successfully.
- Anti-viral properties – lysine may help to boost the immune system and its anti-viral properties may help to treat conditions such as chronic fatigue syndrome, hepatitis, and HIV – more concrete evidence is required to prove this
Talk to a medical professional about lysine supplements before taking them
Deficiency
Groups at risk of lysine deficiency
- People on low protein diets – people who are not eating enough protein foods may not get enough lysine in their diet
- Vegans / vegetarian – people who are on a strict vegetarian diet may suffer from a lysine deficiency if their diet is deficient in protein
- Cold sore sufferers – it is recommend to take lysine during an outbreak of cold sores to speed healing
People in these groups at risk of lysine deficiency should talk to a medical professional about lysine supplements before taking them.
Symptoms of lysine deficiency
Deficiency of lysine is rare, as it is found in so many protein foods. Symptoms of deficiency may include:
- anaemia
- enzyme disorders
- lack of energy
- poor appetite
- irritability
- poor concentration
- hair loss
- bloodshot eyes
- weight loss
- reproductive disorders
Food sources
Lysine in food
| FOOD | AMOUNT | Lysine (mg) |
|---|---|---|
Tuna, canned in oil | 1 can (171g) | 4575 |
Snapper, cooked | 1 fillet (170g) | 4105 |
Halibut, cooked | 1/2 fillet (159g) | 3896 |
Chicken breast, meat only, cooked | 1 cup (140g) | 3689 |
King mackerel | 1/2 fillet (154g) | 3677 |
Round beef, 0% fat, cooked | 100g | 3053 |
Lean veal leg, cooked | 100g | 3025 |
Lean shoulder lamb, cooked | 100g | 3018 |
Romano cheese | 100g | 2941 |
Pink salmon, cooked | 1/2 fillet (124g) | 2912 |
Turkey, light meat only, roasted | 100g | 2845 |
Turkey breast only, roasted | 100g | 2833 |
Lean pork loin chops, cooked | 100g | 2800 |
Yellow fin tuna, cooked | 100g | 2753 |
Turkey leg (meat only), roasted | 100g | 2751 |
Blue fin tuna | 100g | 2747 |
Alaska king crab, cooked | 1 leg (172g) | 2738 |
Turkey, dark meat only, roasted | 100g | 2718 |
Daily intake
Lysine recommended daily intake (RDI)
| RDA | 99mg/kg body weight (infants) 44mg/kg body weight (children) 32mg/kg body weight (adults) |
|---|---|
| TOLERABLE UPPER LIMIT | 300-3000mg |
| TOXIC LEVELS | >10g per day |
Toxicity
Overdosage, toxicity and cautions for lysine
Side effects with lysine are usually rare, although diarrhoea and stomach cramps have been reported in very high dosage, but these have not been shown to be consistent.
Precautions
Precautions
Pregnant or breast feeding mothers, as well as patients with liver or kidney problems, must first consult a health professional before taking lysine supplements
Interactions
Interactions
References
References
- Osiecki H, Meeke F, Smith J, The Encyclopaedia of Clinical Nutrition – Volume 1: The Nervous System, BioConceps Publishing QLD 2004
Last reviewed and updated: 8 May 2024
