B vitamins are necessary for energy metabolism, immune function, neurological function, methylation and protection of DNA, red blood cell synthesis, cardiovascular health, skin and muscle and many other important biological functions. B vitamins are water-soluble so in most cases you will not use what you don’t need from a supplement so unneeded Bs will spill out in the urine. The yellow color in your urine after taking your multi or a B vitamin comes from the Bs. In my opinion, even healthy people in the United States should take a good multivitamin containing at least 100 percent of the RDA. Other folks that have heart disease, diabetes, an autoimmune disease or other medical conditions may require more than the daily recommendations. People taking hormone replacement, birth control, antacids, some antibiotics, arthritic medications or other medications can cause a malabsorption of some B vitamins, particularly B12 and folic acid. A deficiency of these B vitamins can cause serious health problems. So it is important to determine with your doctor or nutritionist your need for therapeutic doses. Vitamin B6 is the only B vitamin that has shown to have the potential to cause nerve damage in doses over or around 500 mg daily so the Nutrition Board of the Institutes of Medicine has set the upper limit at 100 mg daily. http://ods.od.nih.gov/search.aspx?zoom_query=b%206
Finally to answer your question. Take a good full spectrum multivitamin with at least 100% of vitamin B1 (thiamine), vitamin B2 (riboflavin), vitamin B3 (niacin or niacin amide), vitamin B5 (pantothenic acid), vitamin B6 (pyridoxine, pyridoxal, or pyridoxamine, or pyridoxine hydrochloride), vitamin B7 (biotin), vitamin B9 (folic acid), vitamin B12 (methyl or cynocobalamin). The only B vitamin you may see that is never over the RDA is B6 so don't worry if your multi is a little higher in other Bs. Google the food sources for B vitamins found in lean meats, whole grains, green leafy vegetables, brewer's yeast, molasses and liver. I don't recommend the energy drinks for your source of Bs that usually comes with caffeine and sugar. The caffeine and sugar may be the source of energy!