There is one thing that everyone is alluding to in this discussion, but are skirting around. Dr Graham has come the closest - food intake and the body's use of nutrients is a complex relationship. Supplements on their own are useless unless the other vitamins, minerals, enzymes, gut bacteria, etc, are there to make use of them. AND everybody is different in their efficiency in absorbing nutrients.
Many times its certain 'foods' that are more detrimental, no matter supplements or 'balanced diet'. Refined carbohydrates like sugar and white flour are quiet killers. The affects they have on our health undermines everything else we do to improve our situation. Even with judicious consumption of supplements, eye health alone is slowly wrecked by sugar intake (leaving diabetes aside). Excessive grog is another.
I mention eye health as it is one thing that is paramount for us enjoying astronomy.
Good health to everyone,
For curiosity sake, the diet I follow was given to me by an Aunty one Sunday arvo. She said to me while I was getting stuck into a delicious Italian cake "Why are you eating sugar? Is it your birthday?" Not as easy as it sounds...