For many years, nutritional experts have been saying that the only thing taking vitamins does for you is to give you expensive urine. But that has not stopped Americans from spending $30 billion every year on vitamins and supplements, which is probably mostly wasted money, according to a comprehensive analysis of their effects.
The review included randomized trials of vitamins and supplements that examined their effects on cardiovascular disease and overall death rate. It did not include observational studies of vitamin and supplement usage since they are often accused of “healthy user bias.” Those who choose to take vitamins often engage in other healthful behaviors.
Vitamins and supplements that have looked promising in observational studies failed in large randomized trials. In fact, it appears that there is no high-quality evidence that any vitamin or supplement has a beneficial effect on overall death rate.
The recent analysis included studies of 24 different interventions, including 277 randomized trials and nearly a million patients.
The only intervention that had even moderate-quality evidence for protection against all-cause death rate was reducing salt intake, which is the opposite of taking a supplement.
In fairness to the other findings, there was low-quality evidence that omega-3 fatty acids might protect against myocardial infarction and heart disease, and that folic acid might protect against stroke.
On the other hand, there was moderate-quality evidence that a combination of calcium and vitamin D actually increased the risk for stroke.
But all these effects were pretty small.
We should remember that vitamins were generally identified by their deficiency syndromes, like the lack of vitamin C resulting in scurvy and inadequate vitamin D causing a bone disorder called rickets. But there has never been much understanding as to why a megadose of any of these chemicals would give super-benefits to health.
This review only looked at death rates and cardiovascular outcomes, like heart attacks and strokes. It remains possible that vitamins and supplements might improve a person’s quality of life.
Although it is very difficult to separate out the “placebo effect” of taking something that you think will help you feel better, I remember some older patients that I inherited into my practice when I started out many years ago. They had been given shots of vitamin B12 regularly by my predecessor and wanted me to continue them.
These people had Medicare insurance that would not pay for the shots because vitamin B12 shots were generally considered to be quackery. However, some of the patients wanted to pay for these shots privately, finally persuading me to provide them after the patient signed a waver saying that vitamin B12 shots were not initiated or recommended by me.
The knowledge that vitamin B12 is a water-soluble vitamin (such that any excess in the patient’s body could be filtered out by the kidneys and excreted in the urine) allowed me to have a relatively clear conscience about this practice.
If it had been one of the fat-soluble vitamins (A, D, E or K), I would not have considered giving in to the requested large dose shots. Those vitamins can accumulate in the patient’s body fat and may cause serious problems.
Do not expect them to lengthen your life. But if taking vitamins or other supplements seems to make your quality of life better and you avoid excessive amounts of vitamins A, D, E and K, I would not stop you.
But having more money may also improve your quality of life. Based on this study, you might want to save yours instead of spending it on vitamins and supplements.
Do not forget to cut back on your salt intake. That actually might help you.