| The three most studied cases of antioxidants are | | | | extremely difficult to accurately interpret data |
| Vitamin A, including the carotenoids, and vitamin C | | | | from studies that involve smokers because the |
| and E. Although there have been many tentative | | | | act of smoking itself is a confounding variable and |
| proposals, there has been no firm conclusions | | | | increases the risk of cancer. Other studies have |
| drawn, though they have been planted by | | | | found that an increased level of any single |
| implication. | | | | antioxidant is not desirable and two studies have |
| The vitamin A family are a group of insoluble | | | | linked an increase risk of colon cancer with high |
| vitamins that contain retinoids and they regulate | | | | levels of beta carotene in humans. |
| cell division; therefore it is not beyond the realms | | | | The Nurses Health study in America found a |
| of possibility that they may have an effect on | | | | twenty percent rise in breast cancer rates |
| the growth of tumors. Carotenoids consume | | | | between the highest and lowest levels of Vitamin |
| single oxygen and therefore act as powerful | | | | A and carotenoids. These figures were improved |
| antioxidants to minimize damage. It has been | | | | greatly when the women with lower instances of |
| argued that there function may be regulated by | | | | Vitamin A were given supplements. However |
| the immune system, and the healthier the | | | | there were no differences when the same |
| immune system is the more that they will work, | | | | supplements were tried against prostate and |
| however as yet no clinical studies have supported | | | | stomach cancers. However there are positive links |
| this. | | | | between the antioxidant properties of vitamin C |
| Some studies have indicated that retinol or | | | | especially when taken in conjunction with vitamin |
| Vitamin A protects against the incidence of lung | | | | A. In general the results in studies linking vitamin A |
| cancer. Recent data has shown a consistent | | | | and cancer are inconclusive, but they did achieve |
| inverse relationship between various carotenoids | | | | better results with smokers' so there appears to |
| and which are the precursors of vitamin A, and | | | | be a link between the levels of vitamin A and |
| also high levels of beta carotene. | | | | smokers. |
| However Finland has carried out clinical trials and in | | | | What is important is that all of these studies |
| the initial trial they gave 30,000 male smokers | | | | linking vitamins and cancer prevention were |
| beta carotene and vitamin A or a placebo which is | | | | looking at vitamins as part of the whole diet, it |
| a tablet which contains nothing medicinal, but | | | | clearly shows that when the results were tried to |
| which the patient being studied believes will have a | | | | be replicated with single foods that in fact there |
| positive benefit on their health. | | | | was an adverse affect. This once again links to |
| This study was repeated twice since 1994 and | | | | the fact that a varied diet with plenty of fruit and |
| there have been no reduction in the levels of lung | | | | vegetables offers better protection than |
| and smoking related cancers. However it is | | | | enormous consumptions of one super food. |