No, unless you want expensive urine.

No. As long as you eat plenty of fruit and vegetables you shouldn't need any supplements.

Vitamins are vital for good health. Many of us are choosing to take vitamin supplements in our pursuit of a healthier lifestyle. Vitamins are substances that your body needs to work properly and keep you in good health. Most vitamins cannot be made by the body, so they have to be provided by your diet in small regular amounts. Vitamins are found in a variety of foods. There are two types - fat-soluble and water-soluble vitamins. Fat-soluble vitamins are found mainly in some fatty foods such as butter, dairy products, liver and oily fish. If your body does not need fat-soluble vitamins immediately, then they are stored in the liver for future use.3 There are only four fat-soluble vitamins: vitamins A, D, E, K Water-soluble vitamins are found in fruits and vegetables. Unlike fat-soluble vitamins, they are not stored in the body, so you need to eat them more often. If your body has too many water-soluble vitamins, then they are removed in your urine when you go to the toilet. Examples of water-soluble vitamins include: Vitamins B6, B12, C, Folic acid, biotin, niacin, pantothenic acid, riboflavin (vitamin B2) ,thiamin (vitamin B1). For most healthy people, a varied, balanced diet will provide all of the vitamins your body needs, so supplements are not necessary. Eating at least five portions of fruit and vegetables a day will provide most of the vitamins you need. The rest come from meat, fish, eggs and dairy products. Seeds and nuts are also a great source of vitamins. Each vitamin has a different role in the body so you need different amounts of each. People also need different amounts depending on their age, sex, level of activity and their health. For more information: http://hcd2.bupa.co.uk/fact_sheets/html/healthy_eating.html"

No. If you eat good food you will not only get all the vitamins you need but also many other micronutrients and things like fibre which also help your body. You will also find that good food tastes better than pills do.

I think a daily multivitamin isn't a bad idea. The problem is not diet so much as food production. There is definitely soil depletion so many of the minerals are just not there anymore. If you have access to your own homegrown or good local market then it is probably not as important. Many products are 'tampered' with to ensure long shelf life, enhanced appearance and chemical spraying to stop things like sprouting etc.