I’ve visited Nutraceuticals Corp testing facilities and seen Nature’s Way testing, I know they both are extremely thorough. Also well known and I am familiar with their avid testing was NOW, Nature’s Way, Source Naturals, Kyolic and Nature’s Plus.
Nutraceutical Corp who owns, Solaray, KAL, Life Extension (plus others). Nature’s Way who owns Integrative Health. Source Naturals who owns Planetary Herbals. Bluebonnet, Nature’s Plus, Country Life, MRM, Jarrow, Natrol, Natural Factors, Nature’s Answer, Paradise, Solgar, NOW, Kyolic. NOW has a lot of good pricing on their items and you can trust them.
There are others I had liked, but have now been sold to companies I either don’t recognize or don’t know if I trust them. A lot of companies have hit the market, especially for mass market selling. Some could be good but the problem becomes some just exist to make the most money and supply it at a cheap price so it can be sold as cheap as possible. Be wary of the really cheap items.
It doesn’t mean their aren’t others. Solaray/Nutraceutical itself owns a lot of companies now although they are blending some together. I would always trust them as during Melatonin’s first entry and what a hot product it was, there was not enough supply. They turned down 80% of what was brought to them that was certified as being 100% pure melatonin, but double checking in their in house testing it wasn’t. Source Naturals constantly turned down raw materials as not meeting their standards even if it meant being out of stock of product.
I remember a customer walking into my store and being excited they found Goldenseal at a dollar store. Goldenseal is not cheap and I told her do the capsules have a nasty bitter flavor… she tasted one and no, no flavor. If there was goldenseal it had to be a negible amount or none at all. There is also a slight yellow or golden hue to a goldenseal root capsule. Kava extract put on your tongue will make your tongue numb, also bitter, some echinacea extracts can too. Gymnema on the tongue will take away your ability to taste sweets for a bit.
There are others, I just might not be familiar with them. Owning a smaller health food store I relied on dealing with companies I completely trusted because I had built up trust with the community. I wanted to make sure what I was selling was what was really in that bottle. That was my business and I cared.
As for formulas, that’s a different ball game. You still want to trust what is in the product but it might not be the best at performing it’s endpoint. One formula to help blood pressure might have a slight different blend or totally different ingredients and just because the company is trusted, doesn’t mean it’s the best performing. And what works amazingly well on one person might not on another, we can all be different. I relied on feedback from customers and repeat buying to distinguish what was working best for the most people.
Here is a rating of companies that did not pass product testing by NOW.
https://www.nowfoods.com/healthy-living/articles/now-reports-testing-brands-alpha-lipoic-acid