As you can see at the bottom of each post I make, I am Vit D deficient and on Adcal D3 caplets. I thought they might help with the chronic fatigue that has plagued me for years - they didn't! I have started to add cod liver oil supplements to my daily and growing supplement regime and - they work!! I feel better today, and not nearly so exhausted. The container says to take one, I take two. If you are like me, this old fashioned and simple remedy, may just be your answer.