Last update
3/18/2026
Reviewed By
Overview
SCIENTIFIC SCORE
Likely Very Effective
Based on 1 Research
9
USERS' SCORE
Good
Based on 43 Reviews
8.3
Supplement Facts
Serving Size: 1 Vegetable Capsule
Amount Per Serving
%DV
L-Lysine (as L-lysine HCl) (Free Form)
500 mg
**
Top Medical Research Studies
9
We set out to uncover how certain amino acids, particularly lysine, help with cold acclimation. Over three months, 20 men were monitored for physiological changes after being exposed to cold.
We found that continuous exposure led to faster cold-induced vasodilation and improved finger temperature. Notably, lysine was the only amino acid that significantly changed and positively correlated with these improvements in cold response.
In mouse trials, lysine supplementation helped maintain core body temperature during cold exposure, indicating its role in supporting metabolic adjustments to the cold.
We found that continuous exposure led to faster cold-induced vasodilation and improved finger temperature. Notably, lysine was the only amino acid that significantly changed and positively correlated with these improvements in cold response.
In mouse trials, lysine supplementation helped maintain core body temperature during cold exposure, indicating its role in supporting metabolic adjustments to the cold.
Read More
Most Useful Reviews
8
Helps with colds
19 people found this helpful
It helps me; I drink it in courses. It aids with frequent colds on the lips!
Read More
7.5
Prevent cold sores
15 people found this helpful
These are fantastic! They come in easy-to-swallow capsules, unlike the bulky vitamins found in stores. The packaging was perfect. Personally, they help prevent my cold sores; I haven't had one in about nine months since I started taking these. They also make my skin feel fresh and youthful, although I've noticed some oiliness. But that's manageable; just means I need to exfoliate more. They're nearly tasteless! The best L-Lysine vitamins I've ever purchased.
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9
Reduces cold sores
9 people found this helpful
A great alternative to prescription medication for cold sores. I've been taking L-Lysine for over a year, with just one flare-up. I highly recommend this product to anyone dealing with the challenges of cold sores.
Read More
Medical Researches
SCIENTIFIC SCORE
Likely Very Effective
Based on 1 Research
9
- All Researches
9
We set out to uncover how certain amino acids, particularly lysine, help with cold acclimation. Over three months, 20 men were monitored for physiological changes after being exposed to cold.
We found that continuous exposure led to faster cold-induced vasodilation and improved finger temperature. Notably, lysine was the only amino acid that significantly changed and positively correlated with these improvements in cold response.
In mouse trials, lysine supplementation helped maintain core body temperature during cold exposure, indicating its role in supporting metabolic adjustments to the cold.
We found that continuous exposure led to faster cold-induced vasodilation and improved finger temperature. Notably, lysine was the only amino acid that significantly changed and positively correlated with these improvements in cold response.
In mouse trials, lysine supplementation helped maintain core body temperature during cold exposure, indicating its role in supporting metabolic adjustments to the cold.
Read More
User Reviews
USERS' SCORE
Good
Based on 43 Reviews
8.3
- All Reviews
- Positive Reviews
- Negative Reviews
8
Helps with colds
19 people found this helpful
It helps me; I drink it in courses. It aids with frequent colds on the lips!
Read More
7.5
Prevent cold sores
15 people found this helpful
These are fantastic! They come in easy-to-swallow capsules, unlike the bulky vitamins found in stores. The packaging was perfect. Personally, they help prevent my cold sores; I haven't had one in about nine months since I started taking these. They also make my skin feel fresh and youthful, although I've noticed some oiliness. But that's manageable; just means I need to exfoliate more. They're nearly tasteless! The best L-Lysine vitamins I've ever purchased.
Read More
9
Reduces cold sores
9 people found this helpful
A great alternative to prescription medication for cold sores. I've been taking L-Lysine for over a year, with just one flare-up. I highly recommend this product to anyone dealing with the challenges of cold sores.
Read More
10
Effective for herpes
8 people found this helpful
A must-have for those suffering from herpes. Lysine is essential as it prevents the virus from multiplying, combating it effectively. After a three-month course of 1000 mg daily, herpes has ceased to appear. Previously, it would flare up from minor cold or stress. Now, after the lysine course, I’ve been symptom-free for a year!
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9
Child-friendly formula
7 people found this helpful
My daughter constantly dealt with cold sores due to drastic weather changes after moving from Hawaii to Washington. Finding lysine in capsule form was a challenge, and we had been cutting enormous pills in half. These capsules are a lifesaver at preventing outbreaks, making mornings much easier for her to take the necessary supplement.
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Frequently Asked Questions
9
Prevents cold sores
2 people found this helpful
Excellent for cold sores. Great product! I took about four or five capsules when I felt an attack coming on, and fortunately, the cold sore didn't break out! Awesome!
8
Quick recovery
Excellent! I saw during a cold that the effect was remarkable; it puts you on your feet in just three days. I took two capsules at night.
8
Long-term use
Excellent! I have taken this for over ten years, and it has been very helpful against cold sores. Best L-Lysine available. I love the Solgar brand; daily use has helped significantly against cold sores. I take two capsules in the morning.
9
We set out to uncover how certain amino acids, particularly lysine, help with cold acclimation. Over three months, 20 men were monitored for physiological changes after being exposed to cold.
We found that continuous exposure led to faster cold-induced vasodilation and improved finger temperature. Notably, lysine was the only amino acid that significantly changed and positively correlated with these improvements in cold response.
In mouse trials, lysine supplementation helped maintain core body temperature during cold exposure, indicating its role in supporting metabolic adjustments to the cold.
We found that continuous exposure led to faster cold-induced vasodilation and improved finger temperature. Notably, lysine was the only amino acid that significantly changed and positively correlated with these improvements in cold response.
In mouse trials, lysine supplementation helped maintain core body temperature during cold exposure, indicating its role in supporting metabolic adjustments to the cold.
References
- Xue C, Zhu S, Li Y, Chen X, Lu L, et al. Cold exposure accelerates lysine catabolism to promote cold acclimation via remodeling hepatic histone crotonylation. Environ Int. 2024;192:109015. 10.1016/j.envint.2024.109015
Data last updated:
