The Holland and Barrett ones actually only have 23mg of Soy Isoflavones in them, not 750mg - that's the total weight of everything in the capsule. You can still use them, but you have to take quite a few and they're massive capsules! I mean massive! Tesco sell them in 40g capsules.
I used the Holland and Barrett ones this month and they made me ovulate on CD13 (compared with CD19 and CD21 the cycles before). I stupidly also used Agnus Castus because I didn't know you shouldn't use them both at the same time as they cancel each other out, well, apparently not for me! It still worked. I was aiming for an early O and I got it! I hate the uncertainty of not knowing when I'll O as it's anywhere between CD13 and CD21.
I took them CD3-CD6. I was aiming to until CD7, but when I realised I was taking soy and vitex at the same time and shouldn't be, I stopped both out of annoyance!
The Holland and Barrett ones did give me a funny stomach for the first couple of days, but other than that they were fine.
Good luck.
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