Senna is a laxative and, in my opinion, it should only be taken if you don't go often/regularly enough. I fail to see how it can help with weightloss other than a very temporary fix (as in, until your next meal): it does not prevent the actual digestion of the food, which is when your body transformes the food into energy. If anything, it would put you at risk of dehydration and slowly deplete your body of minerals.

The supplements I take are fiber (I supplement with 5 grams a day in addition to the rather fiber-rich diet I am on) under the form of psyllium husk capsules - it helps me feel fuller and help clean the intestines (sorry if I'm being too graphic...). I am also using a lot of teas, in rotation, such as green tea, white tea, rooibos (loads of antioxidants), and various detox teas - they help me reach my liquid intake target and, again, help me feel fuller in between meals. Finally, I also take chromium to help me balance the sugar levels.

I would suggest that you take the time and make a thorough analysis of your diet: are you getting enough carbs and fiber? Nutrition.com - your nutrition resource has all the tools you need, just add into the pantry everything you eat in a given day and see what the result is. You may be eating a bit too much protein, dairy and sugars (from the fruits) and that's what causing your cravings.

To conclude, I wouldn't think there's much value in so-called 'diet pills' or diet shakes etc.
Try to evaluate your food intake and see where it needs to be balanced, as in my opinion this is the key to beat the cravings. I've tried unbalanced diets (low fat, low carbs, low this low that) and they all failed because at some point I just couldn't deal with the cravings, usually for sweets and fried food. I'm now on a very balanced diet with wholegrains, white meat and veggies and I finally feel I can beat the cravings and not think of food all the time. It takes a bit to get to that point though, and some willpower... so don't give up too soon and don't put your hopes in all sort of miracle pills, shakes, bars.

Good luck

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