It's not the same thing.
Depending on the oil, it might contain a certain amount of SDG (a certain number of mg) per serve of oil.
If you want to be sure, get SDG capsules from Vitacost. They contain 40mg per capsule, you get 120 for about $20US. The amounts used in the male pattern baldness studies i've heard of is 50mg per day, so that's pretty close.
Remember - this is an utterly unproven treatment. Although I suppose it has no known side effects and can only do you good otherwise.
It's weird though. It seems Vitacost have a kind of monopoly on the SDG caps from NSI...
Def