Vitamins and minerals are a multi-billion dollar business currently in the US. Our food is plentiful and fortified, and the use of these pills are generally completely unnecessary. Medically, the recommendation for vitamins and supplements--from multiple sources--is as follows: There are no vitamins or supplements needed for typical adults eating a balanced diet with regular sun exposure or consumption of fortified dairy products. That being said, WTSHTF there will be obvious changes to our typical fattened-calf diets. Plan accordingly, but there is very little that some people will do, stretching the valuable resources of the rest of us. Depending on the circle of people that you may need to support, you may be facing less than you were planning too. Our Christian natures will bring more to the table than we might plan for...so there are likely to be shortages of "plenty" and we may be at "adequate" or even worse "survival" diets. Starvation is not an option for the survivalist, and there is no good reason that starvation will plague the knowledgeable prepper. Now that we have established that you will have some food, but not necessarily a balanced diet, we can start to talk about different vitamins and minerals.
Essential vitamins include both long-lived (fat soluble) ones like A, D, E, and K; and shorter-lived (water soluble) ones like B and C. Vitamin A is also called Retinol and is found in meat, some vegetables, and eggs. Vitamin B1 is Thiamine and is found in pork, grains, and yeast. Vitamin B2 is Riboflavin and is found in leafy green vegetables, legumes, almonds, and yeast. Vitamin B3, or Niacin, is found in meats, fruits, vegetables, grains, and yeast. Vitamin B5, Pantothenic; B6, Pyridoxal; and B7, Biotin are all commonly found in many foods and are unlikely to be deficient in any non-starvation diet. B9 is Folic acid and is found in green, leafy vegetables, fruit, grains, and meat. Vitamin D is found in fish, tuna, eggs, and is nicely made by our skin with proper sun exposure. Vitamin E is found in wheats and green, leafy vegetables. Vitamin K is also prevalent in green, leafy vegetables too. Important minerals include Calcium, Iodine, Iron, and Zinc. Calcium is found in dairy products, many vegetables, and eggshells. Iodine is found in [most] table salt [in Western countries]. Iron is found in meats and green, leafy vegetables. Zinc is found in seeds, beans, and grains.
Important deficiencies to worry about depend on the age and situation of a person. Folic acid deficiency can cause an anemia and also birth defects. B12 and Iron deficiencies can also cause anemia and is most often found in strict vegans, which will be a thing of the past WTSHTF. Vitamin C deficiency will affect those with limited stores of fruits and vegetables after they run out. Vitamin D will be important to consider in northern climates with limited sun in wintertime, especially for those that are older adults.
Now, after stopping at my local megalomart, recommendations are pretty easy to make for TEOTWAWKI. Pregnant women need supplementation of vitamins and minerals, specifically B9, or Folic acid. This can be accomplished with either Folic acid supplementation specifically, or a good multivitamin, or both. So, if you have a supply of multivitamins, make sure that any likely child-bearing female is taking one regularly. Older adults should also take a good multivitamin or Vitamin D supplementation. This will help bone strength and prevention of falls. As diets get more "lean" and approach "survival" levels, a good multivitamin will be important for everyone to take at least weekly.
Which one? Good question, really. Turns out there are some differences in your basic store vitamins. Nature Made "complete" is a very good multivitamin that covers all the basic needs of a person across all vitamin and mineral recommendations. The other name brand vitamins are decent, but in almost all the major brands the "women's" versions are a better vitamin and are superior to the basic or "men's" vitamins. If you can get enough, there is no reason you would ever be deficient in a essential vitamin or mineral.
Vitamin C is unique and needs special mention. Anyone suffering from an illness or wound should take Vitamin C twice a day to help with healing. Those with potentially deficient diets or kids should take a chewable Vitamin C twice weekly. Chewable Vitamin C is usually just as cheap as the tablet form, either will do.
Zinc is found in sufficient amounts in any of the multivitamins found on shelves, but there is one group needing additional zinc. Kids with diarrhea lose zinc much faster than adults and are more sensitive to this deficiency. Zinc lozenges are the best form to buy for this specific use. One tablet twice a day will help supply the zinc lost through frequent stools and will increase survival and decrease the length of the diarrheal illness.
So, to sum up:
[JWR Notes: Dr. Bob is is one of the few consulting physicians in the U.S. who dispenses antibiotics for disaster preparedness as part of his normal scope of practice. His web site is: SurvivingHealthy.com.)