Quote:
Several compounds with radical scavenging properties are being studied for cancer chemoprevention. However, it must be noted that, although many patients being treated for cancer use antioxidants in the hope of reducing the toxicity of chemotherapy and radiotherapy, mechanistic considerations suggest that antioxidants might reduce the effects of conventional cytotoxic therapies and a limited number of clinical studies have not found any benefit in these associations. The main antioxidants that are claimed to behave as chemoprotective agents are found in foodstuffs, especially of a vegetal origin, and are ascorbic acid, ergothioneine, green tea polyphenols, and lycopene.
Ergothioneine (not much info on here)
Ergothioneine is a component of white button mushrooms that is considered as an antioxidant with cancer chemopreventive properties.
Ascorbic acid
The antioxidant properties of ascorbic acid (vitamin C) are related to its ability to generate a stabilized radical at its C-3 position because of the operation of the captodative effect. This allows ascorbic acid to react with harmful, more reactive species and prevent their interaction with biomolecules. Ascorbic acid has been recommended for many years to prevent the appearance of gastrointestinal cancers, although a recent statistical study including more than 170,000 patients in risk of this type of cancer showed no evidence of benefit.
Green tea polyphenols
Green tea polyphenols are potent radical scavengers that are being extensively studied as chemopreventive agents. A Phase II clinical assay studied the modulation by these substances of the urinary excretion of 8-hydroxydeoxyguanosine (8-OHdG), an oxidative DNA damage biomarker. The results obtained suggest that chemoprevention with green tea polyphenols is effective in diminishing oxidative DNA damage.
Lycopene
Lycopene is an open-chain carotenoid found in several fruits, especially in tomatoes, which is accumulated in high concentrations in several tissues.It reacts with hydroxyl radicals giving a stabilized, highly delocalized species. Chemoprevention with lycopene has shown definite results in prostate cancer.
While scientists don't have concrete proofs that antioxidants really prevent, reduce or cure cancer, they have been widely used for those purposes. Sometimes, they worked, at other times, they didn't. Anyway, they never caused harm, so why not give them a try?