I haven't needed to diet in years, but a combo of factors (mainly some health issues that prevented me from getting the cardio my body needs) meant I needed to lose some weight. Last year I did Fast Metabolism Diet and lost about 12 pounds in 3 months, which was great, but I gained it back over the holidays and winter. More recently I've been doing Isagenix, which was very successful for one of my close friends, and I managed to lose about 18 pounds in 2 months. Both want you to eat 5 times a day and both follow some rules that are similar to whole30:
* No caffeine, alcohol or soda of any kind (including diet)
* No dairy
* No artificial sweeteners except stevia or xylotol
* No wheat unless it's sprouted

The food rules diverge a bit after that -- Isagenix avoids pork and beef, which was allowed under FMD. The list of acceptable fruits and veggies vary a bit.

Isagenix does a form of intermittent fasting that's very effective (2 consecutive days, twice a month, where you eat something small every hour you're awake, resulting in about 500-600 calories in the day). Isagenix is, at its core, a multi-level marketing thing. They sell you shakes and supplements. (And some of the rules are contrary to their product ingredients -- for example, there is whey in the shakes.) But it's working so I can't argue!