If there was one best supplement to take, would you take it? Of course, but the problem is that everybody is different. There is no magic pill. The thing is that there is no one herb or supplement I can recommend to work for everyone.
Is Vitamin D the best supplement to take?
When someone says, “I took Vitamin D and all my problems were gone!” They were likely deficient in Vitamin D. What if you saw what a difference it made to that person and you take Vitamin D, and Vitamin D deficiency isn’t your problem, then it will not help. The downside is excess Vitamin D can be toxic.
Unfortunately, signs for a vitamin deficiency are often the same as signs for vitamin toxicity. Low iron for example can cause fatigue, while high iron can also cause fatigue.
Some vitamins are less of a problem because they are water-soluble, like B-vitamins. These are great where chronic stress is underlying, but you need to be aware of the different forms of B vitamins because some people have a gene which interferes with its metabolism. There is a pathology test I use in the clinic to determine if you have this gene.
Is Ashwagandha the best supplement to take?
Same with herbs. It’s all over the web about Ashwagandha being fantastic for stress and anxiety, but if you are allergic to nightshades or have a family/medical history of hyperthyroid, then it could cause serious thyroid problems.
My point is: get a professional assessment and professional advice about natural supplements.
The only general tips I give are based on diet and lifestyle. Even then, one must be wary, like I wrote about the Low fodmap diet blog.