Supplement Fillers That You May Want to Avoid
Vitamins and supplements capsules often contains fillers. Read the label for "other ingredients" and you will see what kind of fillers they have. While fillers sometimes can not be avoided. There are certain fillers that you may want to avoid.
Some of these fillers are so common that you might not be able to find the pure supplements in your local vitamin chain stores. Because these stores cater to the mass market that may not always be so informed, they often contain the less expensive supplements that contain these fillers. For higher quality and pharmaceutical grade supplements, you may need to get them from your doctor's office or go online to specialty supplement manufacturers.
Avoid Titanium dioxide
Titanium dioxide is often use as a white pigment in sunscreens. And some people are already complaining about the putting that stuff on their skins. But did you know that some supplements also contain titanium dioxide? And we are eating those. Yes, I once bought a magnesium citrate supplement and later saw titanium dioxide as "other ingredients". Needless to say, I promptly returned it the same day. I'm guessing they are using that to make the supplement look "white" because consumers are used to magnesium looking white.
Another possible ingredient is silicon dioxide used as an anti-caking agent. Personally, I don't think silicon dioxide is as bad as titanium dioxide. You can read more about it at LivingStrong.com
When taking supplements by capsules, it is often difficult to avoid any extra ingredients in it. At the very least, they have to use celluose and water to make the capsule. You might want to consider liquid formula or some powered formulas for greater purity.
One professional brand named "Pure Encapsulation" makes capsules that are quite pure and has very little filler.
Avoid Gluten and wheat
There is no reason why there need to be wheat and gluten in your supplements. While everyone should avoid gluten in their supplements, this is especially essential if you have a gluten sensitivity.
The same can be said of other food sensitivity like dairy, corn, soy, and eggs which along with gluten are common food allergens. So you may want to avoid supplements containing those if you have a sensitivity to them.
I know it is pretty difficult to avoid soy, since soy lecithin so ubiquitous and is sometimes needed as an emulsifier. I did a blood test that determined that I don't have a soy sensitivity, so I will occasionally take supplements that contain soy. Soy lecithin is not the worst filler in the world. See article Harmful or Harmless: Soy Lecithin.
Avoid Artificial Colors
Some people are also sensitive to artificial colorings and/or flavorings. Some children (especially those with ADHD) have been known to react to the artificial coloring in the supplements. Ironically, it is often those supplements made for kids that often have these artificial colors and flavors in order to get the kids to take them.
Avoid Magnesium Stearate
Speaking of magnesium, you want to avoid fillers containing magnesium stearate. This was one of the four vitamin fillers that Dr. Axe says to avoid in his article here. But Chris Kresser is not so concerned. Whether you believe magnesium stearate is harmful or harmless, I rather not consume things that the body don't actually need.
I know there are benefits to taking magnesium supplements. But as I wrote in another article, the form of the magnesium is important. Magnesium stearate is not the supplemental form of magnesium that is taken for health benefits.
Here, magnesium stearate is used purely as a flow agent to aid the manufacturing process so that manufacturing can produce products are lower cost.
Avoid hydrogenated oil
Partially hydrogenated oils are "trans fat". You've probably heard by now to avoid trans fat in foods. So the same is true of supplements. Sometimes you might see hydrogenated soybean oil for example in supplements. While the small amount that is in the supplements might not be the worst thing in the world, with two different supplements side by side and all other things being equal, I would take the one without the hydrogenated oil.
Some supplements (for example fish oil gummies) contain corn syrup, sugar, and gelatin. Those are just there to make the supplement taste good so that kids would eat it. You don't want fish oil gummies. Get a high quality liquid fish oil or cod liver oil and keep it in the fridge to avoid the oil from going bad.