Spend 60-70% of your time cycling (i.e. for every 10 hours training cycle 7 hours run 2 hours and swim 1 hour) This is only a very basic guide line for injury prevention and you will get some cross over in fitness, the better you are on a bike your ironman marathon will be easier to complete.
People with liver disease and high alcohol intake may be at risk for liver toxicity from vitamin A supplementation. Vitamin A toxicity may lead to intrahepatic cholestasis, where bile cannot flow from the liver into the intestines. Vitamin A may cause low blood pressure. Caution is advised in people with low blood pressure or in those taking drugs or herbs and supplements that lower blood pressure.
Water-soluble vitamins. Water-soluble vitamins travel freely through the body, and excess amounts usually are excreted by the kidneys. The body needs water-soluble vitamins in frequent, small doses. These vitamins are not as likely as fat-soluble vitamins to reach toxic levels. But niacin, vitamin B6, folate, choline, and vitamin C have upper consumption limits. Vitamin B6 at high levels over a long period of time has been shown to cause irreversible nerve damage. A balanced diet usually provides enough of these vitamins. People older than 50 and some vegetarians may need to use supplements to get enough B12.