The Dark Side of Curcumin

The Dark Side of Curcumin

In This Article

Whole Herb or Extract?

Once again, science tells us the risks of using the turmeric extract curcumin, rather than whole turmeric root.

Curcumin is just one of some 300 constituents in turmeric root. It makes sense that when you isolate one of turmeric root’s constituents, it will act more like a drug (aka with side effects) and not be recognized by the body as the food or spice that has been safely used for thousands of years.1

I am not suggesting that isolated curcumin is without potential benefits. But, according to Ayurveda and now new science, there is always a risk when we isolate an “active ingredient” to make a drug. This drug may be more potent and even cure disease, but all such drugs have side effects. We are all made well aware of such side effects listening to the TV drug ads!

Many experts falsely label curcumin as the “active ingredient” of turmeric, but many studies find that whole turmeric root outperforms curcumin in many ways and now research finds there may be risks associated with using curcumin alone!1

Curcumin Side Effects

  1. Curcumin (but not whole turmeric) blocks iron absorption and is linked to anemia.4
  2. Curcumin, at a low dose, has antioxidant properties. However, curcumin at a higher dose incurs free radical damage as reactive oxygen species.1
  3. At a low dose, curcumin boosts stem cell activity. However, curcumin at a higher dose blocks stems cells and is toxic.2 Read more here.
  4. Curcumin has been shown to be supportive in many disease processes, but not without side effects like oxidative damage, toxicity, gastrointestinal irritation, and more.1,3

See also Turmeric Health Benefits Outperform Curcumin (Turmeric Extract)

Iron Deficiency Linked to Curcumin

Phenols in curcumin bind ferric iron (Fe3+) to form ferric-curcumin complex. In mice, liver hepcidin and ferritin expression were strongly suppressed and iron concentrations in the liver and spleen were reduced by over 50% by curcumin. Curcumin represses synthesis of hepcidin, one of the peptides involved in iron balance, and has potential to induce iron deficiency.3

In a 2006 study, turmeric powder was compared with chili powder for their effect on iron absorption. Chili powder, even though it had half (25 mg) the phenols of turmeric (50 mg), blocked iron absorption, while whole turmeric root did not.4

In an earlier study, intake of 20-50 mg total polyphenols from black or herbal tea (containing polymers of flavonoid-gallic acid esters and monomeric flavonoids) reduced iron absorption from an iron-fortified bread roll by 50–70%.4

Many foods high in polyphenols and phytic acids have been found to compromise iron absorption. Phytates or phytic acids are implicated in many food intolerances, such as sensitivity to wheat, nuts, and grains. Phytates are anti-nutrients that help block bacterial enzymes from gobbling up the grain while the grain or seed lies dormant, awaiting germination in the spring. Concerns around phytates are that they block absorption of minerals like iron, calcium, phosphorus, and zinc.

Primary sources of iron-blocking polyphenols are vegetables and beverages like wine, herb tea, black tea, and coffee. These strongly inhibit iron absorption in a dose-dependent manner.4 Curcumin’s phenols seem to have this effect, while phenols in whole herbs such as turmeric seem not to.

See also Iron Deficiency Anemia? Restore Your Ferritin Reserves

One study compared a high-phytate diet (including grains) with a low-phytate diet. After eight weeks, the high-phytate group saw a 41% increase in bioavailability of iron in the blood, suggesting that the body may be adapted to digesting foods with more phytates.5

While some say a high-phytic acid diet is linked to osteoporosis, there are studies showing a high-phytate diet will increase bone density. It may be that phenols act differently in the body based on how we consume them, and the many other factors in each phenol-carrying food or herb.

See also The Benefits of Antinutrients + Naturally Occurring Food Toxins in Your Diet

Conclusion: Whole Foods, Phenols + Food Combining

Whole foods may have properties or constituents that in isolation may block absorption of certain nutrients. When you take a constituent out of a plant (like curcumin from turmeric root), you run the risk of that constituent causing drug-like effects (both positive and negative). This requires navigating drug-like side effects not present when consuming the whole plant, root, or herb, as we suggest at LifeSpa.

What about phenols? Studies show cultures that eat foods high in polyphenols and phytic acids are abundant and that they do not experience nutritional deficiencies.6 You may want to avoid overconsumption of coffee, wine, and herbal extracts, but don’t shy away from whole herbs like turmeric root due to the phenol and phytic acid content!

A whole herb is great; whole herbs in combination can be even better! At LifeSpa, we combine turmeric root (16 parts) to black pepper (one part), matching traditional use of turmeric as part of Asian curry. This combination has been studied to safely boost turmeric absorption. Learn more about our Turmeric Plus here and start enjoying the many benefits of this whole herb!



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Dr. John

2 thoughts on “The Dark Side of Curcumin”

  1. My browser doesn’t show the sources implied by your footnotes. I’d particularly like to see the research articles linked to the iron depletion and oxidative damage caused by excessive curcumin. Thank you for the information.


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