Customer Ratings & Reviews

100% authenticOur products are sourced directly from brands or authorized distributors.Show more

4.8

Based on 3,582 ratings

2,936

457

146

Write a Review

What customers say

Top positive review

iHerb customer

Posted on Jul 29, 2016

Malaysia

1,137

► The Only High Potency Zinc Supplement FDA Approved Safe For Human Nutrition

OptiZinc, aka L-OptiZinc, is the only high-potency zinc supplement FDA approved safe for human nutrition. OptiZinc is also an approved form of Zinc for use in the EU in food supplements. OptiZinc is a forms of methionine-bound zinc that increase the bioavailability of Zinc. Methionine is the amino acid best absorbed by the body. OptiZinc is standardized to 20% Zinc, consists of Zinc bound to the more bioavailable form of methionine. OptiZinc is absorbed better, retained longer and are more effective than other Zinc supplements tested. I highly recommend this high quality product manufactured by Source Naturals with reasonable price offered by iHerb. Best wishes and good health to everyone!

(3,545)

iHerb customer

Posted on Oct 21, 2025

United States

nice product!

Verified purchase

I’ve been using the Source Naturals OptiZinc® (60‑tablet) supplement for a couple of months now and wanted to share my experience. Right away I noticed the tablets are easy to swallow and the quality feels solid—no weird after‑taste or upset stomach. It’s not the cheapest zinc supplement out there, but considering it uses a premium zinc form (zinc‑monomethionine) and includes copper for balance, I feel like it’s worth the extra cost. Since starting it I feel like my immune response has improved (fewer colds), my skin texture seems better, and I have more energy overall. On the flip side, because it’s a higher dose of zinc I make sure to take it with food and monitor other nutrients, but overall I’m quite pleased and would recommend it to anyone wanting a reliable zinc supplement.

iHerb customer

Posted on Sep 24, 2025

United States

High quality and recommended

Verified purchase

I'm usually a fan of source naturals, and the Zinc is a no exception. taking it for a viral infection and helping out alot.

LesyaGA

Silver

Posted on Mar 12, 2026

Azerbaijan

235

Good

Verified purchase

This supplement has excellent quality and feels very well made. The ingredient list is clean and easy to understand, which gives confidence in the product. The size of the capsules is convenient and not difficult to swallow. The recommended dosage is simple to follow and fits well into a daily routine. Overall, the benefit is noticeable, and the taste is mild and not unpleasant.

ANWAR

Gold

Posted on Apr 25, 2025

Bahrain

404

418

670

great

Verified purchase

very good quality and nice package very good composition for immunity and it's effect and potency on my heath as a very good antioxidant important for our health gentle on stomach no any burning sensation i took it with my collagen at morning time with my green drink thank you iherb I like everything

Andrew

Silver

Posted on Apr 2, 2026

Singapore

135

Great quality and easy to take

Verified purchase

Really happy with this zinc supplement. The tablets are easy to take, the quality seems very good, and it has been simple to add to my daily routine. A reliable product that feels like good value, and I would purchase it again.

iHerbCustomer

Silver

Posted on Feb 7, 2026

China

113

Very good

Verified purchase

I like it especially because tablets size are small and it’s easy to use. Good support for immunity. Great quality of ingredients. Good dosage. I can see good effect for my hairs. It also contains cooper so it’s perfect for me

iHerbCustomer

Silver

Posted on Jan 30, 2026

China

182

Good

Verified purchase

I like this zinc, it also contains copper so it perfect for me. High quality of ingredients. Good dosage of mg. It has very small size of pills so it’s easy to take

iHerb customer

Silver

Posted on Jul 30, 2025

Croatia

156

Verified purchase

Source Naturals is one of those companies that carrie this form of zinc, which is great for athletes before sleep, together with magnesium. The size of the package is long lasting, mg per tablet right about what's needed, the quality is known, you can't go wrong.. Zinc is essential for immunity, skin, hair, nails.

supplement-geek

Silver

Posted on Oct 5, 2025

Israel

122

High-Absorption Zinc That Really Supports Immunity and Skin Health

Verified purchase

This OptiZinc from Source Naturals is one of the best zinc supplements I’ve used. It contains zinc monomethionine — a chelated form that’s much better absorbed than regular zinc oxide. After a few weeks of consistent use, I noticed stronger nails, clearer skin, and a better immune response overall. It also helps with post-workout recovery and hormone balance when taken regularly. Each tablet provides a clean 30 mg dose, which is perfect for daily maintenance. The tablets are small and easy to swallow, and I haven’t experienced any stomach upset, even when taken without food. I also appreciate that the formula includes a small amount of copper to help maintain mineral balance. The bottle arrived from iHerb sealed, fresh, and well-packed. With 240 tablets per bottle, it’s an excellent long-term value. If you’re looking for a highly bioavailable zinc supplement that actually delivers noticeable results, this one is a great pick.

iHerb customer

Posted on Jul 17, 2025

Thailand

Great quality compare to price

Verified purchase

This is a high-quality zinc supplement that uses a special form of zinc (zinc monomethionine sulfate) for better absorption, combined with copper to keep your minerals balanced. Each small, easy-to-swallow tablet delivers a solid 30 mg dose of zinc, making it effective for immune support, skin health, and energy.

Customer Ratings & Reviews

What customers say

Top positive review

(3,545)

Rating

Languages