Here's a great, informative site given from a balanced perspective....

Mercola - a GP who embraces a natural and holistic approach to health and wellbeing.  Dr Mercola is not afraid to expose immoral practices and how some "health promoting" companies will do anything to maintain their wealth. 

And some others to be aware of...

Organic Consumers Association  - This organisation campaigns to maintain people's rights to buy organic food and to have food such as GMO and irradiated food clearly labelled so we have a choice on what we eat.  They also help support the rights of people to buy vitamin C and other supplements in the doses we want to.  Unfortunately, there are organisations (such as Codex Alimentarius below) who try to stop this - the reasons are highly political and seem to me to serve no benefit to mankind

Codex Alimentarius - an organisation that promotes the use of pesticides, chemicals and additives and unnatural ways of producing food.  It has classified nutrients as toxins that must be regulated (!)  Unfortunately, this organisation has managed over many years to increase its power and wants to bring in regulations that are highly detrimental to health, but highly advantageous to the pharmaceutical industry, pesticide producers, biotechnology (GMO) and chemical industries.