Low Carb: Reduce carbohydrate intake as many feel carbs = fat. Not necessarily true, but aim it get energy from protein and fat, over carbs. Unfortunately, you need carbs, so reducing them too much leaves a person flat and feeling empty. With that said, the idea is that carbs are inherently bad, so avoid them.
Ketogenic: Works by kicking your metabolism into “starvation mode” where it will start cannibalising the fat stored on your body vs the energy from the food you eat.
Low Fat: Many believe fat you eat is basically slapped onto your body, so they avoid eating it. This has been debunked decades ago. There’s also good fats vs bad fats (trans fats).
IF: Employs the growing theory that eating within a window (usually 8-10 hours, so not a “few hours”) is ideal for both weight management, but also general health (some argue there are lots of systemic downsides to eating outside this window, like cancer and other long term ailments). Dr. Ronda Patrick is a huge proponent and has some amazing scientific research on the topic: https://www.foundmyfitness.com. Sadly the internet has left out those bits and treats it essentially as a way to generally eat less.
Weight Watchers: Calories counting at its finest, which has very poor efficacy btw. But the only one that doesn’t so much as control what you eat (their meals are shit), but more of how much. None of the other diets aim is to control the amount of food ingested.
Paleo: The idea that modern food is essentially shit. So one goes back to the basics and tries to eat as “primal” as possible. Basically food that is slaughtered and grown goes on your plate. No yogurt, no milk, no cereal, no processing of any kind. You live off nuts and potatoes and meat. Depending on
Keto for weightloss is a meme. It is supposed to help reduce seizures epileptic children not help adults loose weight.
Weight Watchers is subscription based weight loss, the primary goal is to keep the dieter feeling like it will take just one more month to reach that goal, but they never will ;)
Paleo is just a huge joke, in span of the Paleolithic era humans went from being field apes to full on farmers. So a true paleo diet could include anything from raw rabbit to a burger on baked bread.
