Garlic and Onion Toxicity?

Yazmin

Good morning:

I have googled garlic and onion toxicity just out of curiosity, but came up with some contradictory answers. I try to include garlic and onion in my everyday diet, and I always thought of those as highly beneficial.

Can someone tell me how much garlic/onion is too much (I remember reading on these board about someone who said they eat like 5 or more garlic cloves a day. Apart for the most obvious side effect of such a practice, I wonder if this could cause stomach irritation, among other problems).

How much garlic a day would be too much?

And finally, I have read about the advantages of "aged" garlic. Could someone give me more information about what "aged" garlic  is?

Thank you.