Viz: What popular supplements are worth taking?

Information is Beautiful: Snake Oil?
by Pamela Ocampo

The FDA defines a dietary supplements a product that is "taken by mouth [and] contains a "dietary ingredient" intended to supplement the diet." Vitamins, minerals, herbs or other botanicals, amino acids, and other substances can be produced in supplement form. There is a myriad of supplements available today. This large selection makes it hard to decide what works and what doesn't.


This visualization shows the relationships between health supplements and scientific evidence. The bubbles represent popularity vs. scientific evidence for many popular supplements. The higher a bubble, the greater the evidence for the supplements effectiveness.

Some supplements have more than one bubble with different effects. In order to see the effect related to a supplement, hover your mouse over the bubble. Some supplements affect a range of conditions, but the evidence quality varies from condition to condition. For example, strong evidence exists that recommends Green Tea is good for cholesterol levels, but evidence for its anti-cancer effects is conflicting. If you click on any one of the bubbles, you are linked to the research paper providing evidence of that supplement's effects.

The y axis indicates effectiveness or strength of the evidence from none to strong. The x axis is the alphabetical order of the supplements. Bubbles higher than the "worth it" line are supplements that have valid scientific evidence behind them.

The visualization does a decent job of giving the viewer an overview of which supplements are worth taking, but at a glance the user may not be aware that you have to hover over each bubble to see what effect the supplement has. It may also be confusing to see multiple bubbles for the same supplement on both sides of the worth it line. It would be better the effect related to each bubble was displayed by default. The bubble size may also be confusing to the user. Instead of indicating effectiveness, a bigger bubble indicates the number of Google hits for the supplement.

Overall, this visualization is a good guideline but it is still recommended that as an individual, one do ones own investigations to see if the research and experiments performed on the supplements effectively test the benefits of each supplement. It is also not necessary to take a vitamin or mineral supplement if one does not have a deficiency for that substance.