Last update
5/5/2026

Overview

SCIENTIFIC SCORE
No researches found
N/A
USERS' SCORE
Good
Based on 2 Reviews
8.4
Supplement Facts
Serving Size:  1 Vegetarian Capsule
Amount Per Serving
%DV
Vitamin C (from ascorbic acid, camu-camu berry extract)
30 mg
33%
Quercetin (as quercetin dihydrate)
250 mg
**
Optimized Food Blend[onion (bulb) (extracts), bitter orange bioflavonoids (peel and fruit), apple (fruit)
220 mg
**
Camu-camu extract (wildcrafted berry)
50 mg
**
📅 Last updated:

Most Useful Reviews

9
Fatigue reduction felt
2 people found this helpful
Quercetin has been excellent for my entire health following COVID-19 with symptoms of weakness and increased fatigue. After 1.5 weeks, my lethargy diminished significantly, and after three weeks, I felt no fatigue at all. I will continue using it as protection against oxidative stress—definitely a product I highly recommend!
Read More
6
Energy levels up
This Optimized Quercetin by Life Extension has been key to my well-being, supporting my immunity and enhancing my overall health. The convenient vegetarian capsules allow me to easily manage my intake, and long-term use has noticeably improved my energy levels, while also reducing fatigue and stress.
Read More

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User Reviews

USERS' SCORE
Good
Based on 2 Reviews
8.4
  • All Reviews
  • Positive Reviews
  • Negative Reviews
9
Fatigue reduction felt
2 people found this helpful
Quercetin has been excellent for my entire health following COVID-19 with symptoms of weakness and increased fatigue. After 1.5 weeks, my lethargy diminished significantly, and after three weeks, I felt no fatigue at all. I will continue using it as protection against oxidative stress—definitely a product I highly recommend!
Read More
6
Energy levels up
This Optimized Quercetin by Life Extension has been key to my well-being, supporting my immunity and enhancing my overall health. The convenient vegetarian capsules allow me to easily manage my intake, and long-term use has noticeably improved my energy levels, while also reducing fatigue and stress.
Read More

Frequently Asked Questions

9
Fatigue reduction felt
2 people found this helpful
Quercetin has been excellent for my entire health following COVID-19 with symptoms of weakness and increased fatigue. After 1.5 weeks, my lethargy diminished significantly, and after three weeks, I felt no fatigue at all. I will continue using it as protection against oxidative stress—definitely a product I highly recommend!
6
Energy levels up
This Optimized Quercetin by Life Extension has been key to my well-being, supporting my immunity and enhancing my overall health. The convenient vegetarian capsules allow me to easily manage my intake, and long-term use has noticeably improved my energy levels, while also reducing fatigue and stress.
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