Thought I might bring this up. My father advised me to take chlorella when I was in my 20's. Its always been one of those sup's I've taken ever since.
Chlorella is derived from algae. And serves a similar purpose as DIM. Now I wouldn't take it in place of DIM but together it seems the two are a powerful combination when it comes to liver health and managing estrogen.
Here a short excerpt about about the benefits of chlorella.
Chlorella is a single cell fresh water green microalgae that is loaded with nutrients. It contains more nucleic acids (RNA/DNA) than any other food, which gives it a lot of energy producing potential. It is a great supplement to boost any diet lacking in green vegetables. It's great for children, and it has a wide variety of useful nutritional applications, which include supporting natural detoxification, digestive health, immune function, inflammation reduction, antioxidant function, estrogen balance, cholesterol metabolism, and circulation.