So, I've started this new diet; I've opted to try to lose weight and overall be healthier on the Keto Diet. On this diet, my caloric intake comes mostly from Fats and Proteins (it is, by definition, a "high fat, moderate protein, and low carbohydrate" diet), which means that I've effectively cut all sugar out of my diet. That doesn't mean I can't have sweet things, it just means that the sweetness can't come from sugar. Sucralose, Stevia, and Erythritol are all good alternatives to sugar, and to be honest my mood has noticeably improved over the 6 days so far that I've been doing Keto.
"Lose weight by eating more fats?" you might ask. Yes, that is effectively the gist. Normally people (in North America, at least) get the majority of their calories from processed and natural sugars. Your body priorities this as a source of calories because, well, it's easier than metabolizing fats. The intent, or 'theme', of the Keto diet is to starve your body of the Carbohydrates that it may be used to metabolizing, so much so that it looks at the fat content in your diet and says "OK, well I guess I'll take what I can get" and starts to break down fats for calories. When your body gets used to metabolizing fats and used to having a lack of carbohydrates, you will find it easier to wean down your calorie intake. This is because as you gradually ingest less fats your body looks at it's fat stores and says "hey, I can use that!", and so weight loss is achieved.
Effectively you're forcing your body into a starvation mode; NOT from lack of food or nutrients but through acclimatizing the body to burning fat for fuel and then burning the fuel that has been stored. It's kind of a biological hack, though many people switch to Keto diets on a permanent basis. I've even read that permanently switching to Keto has helped Type 2 Diabetics avoid having to medicate for insulin deficiency (which effectively "cures" Type 2 Diabetes). As a self-titled tinkerer and hacker, I think this is all very exciting and fascinating. I'm still learning a lot about the science behind it all and ways to keep true to the diet, so many of the terms in this post may, in fact, be incorrect. I apologize for any misinformation that this post may cause.
I've heard, both from online accounts and from fiends that have done the Keto diet, that fundamentally changing your metabolism like this causes your body to become satiated more easily (from the months of calorie intake from rich fats and proteins). So once you've made the transition it becomes easier to stay on target.
Now with all this being said, the transition is by no means an easy one and you have to keep exhaustive track of your nutrient intake throughout the day. The challenge becomes to both find the "macros" that your body requires, and then to adhere t them as closely as possible.
These "macros" are calorie intake from carbohydrates, from fats, and from proteins. Too much carbohyrate and you're out of ketosis, burning carbs and storing fats (gaining weight). Too many proteins and your body uses those for fuel and stores fats (gaining weight). Too little protein and you're losing muscle mass (getting weaker). Too many fats and your body burns what it needs to and stores the rest for later consumption (gaining weight).
The last one of these is harder to do, especially once you get to metabolizing fats, because you get satiated from fats to the point where you just don't feel like eating more. Protein intake, especially, is a fine line that's hard to keep track of. Your required protein intake depends on your lean body mass and your level of activity throughout the day.
This is my current diet challenge, with a target of losing ~45 lbs. Wish me luck!