DIM (
diindolylmethane) is a breakdown product of indole-3-carbinol, a compound found in broccoli, cauliflower, cabbage, brussels sprouts, and other cruciferous vegetables. It is popular as a
dietary supplement and is claimed to be useful for a variety of different purposes, most of which are related to estrogen metabolism or cancer.
(Click Benefits of DIM for more information on what it is used for, including additional uses.)
DIM is formed when indole-3-carbinol (I3C) is digested in the stomach. It is thought that I3C affects the metabolism (breakdown) of estrogen hormones in the body, increasing the levels of certain "good" estrogen compounds while decreasing the levels of "bad" estrogens. Also, I3C may act as an anti-estrogen and may inhibit the growth of certain types of cancer cells. It is likely that I3C also works in several other ways that are not fully understood.
It is often claimed that DIM works just like I3C, although research suggests that there may be important differences between the two compounds. For instance, some studies have suggested that DIM may have different effects on estrogen metabolism compared to I3C and that DIM may have both anti-estrogen and estrogen-like activity. Currently, there is much debate (mostly among manufacturers and patent holders of various DIM and I3C products) about which compound is best and whether DIM provides the same benefits as I3C.
There is not enough evidence to know for sure if it really works for any use
(see Does DIM Work? for more information).
A safe and effective dose for the supplement has not yet been established.
Contrary to what many people believe,
dietary supplements can cause side effects. However, at this point, little is known about the potential side effects of DIM in humans.
(Click DIM Side Effects to learn more, including potentially serious side effects that you should report immediately to your healthcare provider.)
It is probably safe for many people at reasonable doses (such as the amounts normally found in foods). Some people may be more likely to experience problems due to the supplement. Therefore, you should talk with your healthcare provider before taking this supplement if you have:
- Liver disease, such as hepatitis, cirrhosis, or liver failure
- Kidney disease, including kidney failure (renal failure)
- Cancer (or a history of cancer)
- Any allergies, including allergies to foods, dyes, or preservatives.
Also, let your healthcare provider know if you are:
Make sure to tell your healthcare provider about all the medicines you take, including prescription and non-prescription medicines, vitamins, and herbal supplements.
(Click DIM Safety for more information, including any available warnings and precautions.)
What If I Take an Overdose?
It is not known exactly what to expect from a DIM overdose. If you think you may have taken too much, seek medical attention immediately.
Refer to the label of your individual product for information on how to best store the supplement. Keep all medications and supplements out of the reach of children.
