I've had the exact same problem for years and after much fiddling around I too recommend vitamin D3. it's the same as produced by the body from sunlight. eat

I've had the exact same problem for years and after much fiddling around I too recommend vitamin D3. it's the same as produced by the body from sunlight. eat more fruits and vegetables. maybe take a multivitamin and fish oil daily. exercise regularly. and get enough sleep FOR YOU. some people need more than others. I don't think it's any surprise that people are much less sick in the summer. People are in the sun much more in summer and hence have higher levels of vitamin D in their blood stream. I personally feel that sufficient vitamin C and zinc (for men especially) are also important. But taking D3 at 2000-5000 daily is perfectly safe and certainly beneficial. Why else would your body produce after exposure to UV radiation?