Low-carb eating gets a lot of attention, and most of it comes down to one question: does cutting carbohydrate help you lose more weight than other ways of eating? The research has been run many times, so we can look at what it actually found rather than at the loudest claims.
The short version: in the first months, low-carb diets tend to show a slightly bigger drop on the scale. After a year or two, the gap shrinks to something too small to matter for most people. Both kinds of diet work for some people and not for others, and that difference between people is far bigger than the difference between diets.
Cutting carbohydrate makes the body hold less water for a while, and many people also eat less simply because a whole group of foods is off the menu. That can make the first weeks look dramatic. As the water settles and everyday life returns, results between diets move closer together. Over longer periods, how well someone can keep going tends to matter more than the label on the diet, though the trials cannot fully separate the two.
The reviewers noted that none of the trials was at low risk of bias: many were small, could not blind participants and lost people along the way. Evidence on side effects over two years was too limited to draw conclusions. For people with lipid disorders (such as high cholesterol), the Cochrane authors advise caution about low-carbohydrate, high-fat diets. Research on keto-style diets in particular is mixed, and long-term data is thin.
Low-carb is one option that works for some people, not a better diet for everyone. Pick the way of eating you can enjoy for years.
This is not medical advice. If you have a medical condition, are pregnant or breastfeeding, have or have had an eating disorder, or take medication, talk to a doctor or dietitian before changing how you eat. That matters most for diabetes treatments such as insulin, where cutting carbohydrate can lead to low blood sugar unless medication is adjusted with professional support, and for blood pressure medication. Weight is also only one of several health goals; a diet is never a reason to eat below public minimums or to skip meals you need.
If you are curious about low-carb, try a version you could imagine eating in a year, with plenty of vegetables, beans, nuts and whole foods, and see how you feel. If it is not for you, that is fine: the evidence says other ways of eating can do just as well.