There are a number of research papers conclusively recommending low carbohydrate diets over low fat diets. A few examining several past studies have found greater weight loss resulting from restricting carbohydrate consumption compared to when cutting down fat. http://www.thelancet.com/journals/landia/article/PIIS2213-8587(15)00367-8/abstract

Sticking to a low carbohydrate diet for 12 months gave better results (according to the above) than sticking to a low fat diet. Additionally being more disciplined in a low fat diet did not appear to improve weight loss. For a low carb diet, the extra strictness paid off in more weight loss.

So why aren’t many people aware of this, or following the diet? 

There is a lot of negativity about low carbohydrate diets following the Atkins diet and numerous fad diets that proposed focusing on meat and protein. The body clearly needs other nutrients, including a number of vitamins that can only be got from vegetables and fruit.

This is where the low carbohydrate diet becomes more sophisticated than Atkins. It does not state that no fruit sugars should be consumed or that no carbohydrates should be. It just suggests fewer carbohydrates, particularly in starchy low-fiber form, should be eaten. Fruit should still be consumed and should in fact be a main source of carbs. A diet should still be balanced, but that doesn’t mean each nutrient should make up an equal proportion of diet.

What is the research around this?

Fats are not all necessarily harmful, but trans-fats and saturated fats are still considered best avoided  – (Harvard research in 2003  – http://isites.harvard.edu/fs/docs/icb.topic982606.files/Mensink_-_Dietary.Fats.LDL.HDL.TG-Metaanalysis.pdf).

Low-carb or low energy diets are at least equally effective for losing weight than low-fat diets: http://jamanetwork.com/journals/jamainternalmedicine/fullarticle/409791

Other articles, including a recent 2016 article by Hu et al . show that low carbohydrate diets are more effective than low fat diets. They also point to the decrease in fat consumption as percentage of overall nutrition in the US from 1970 to present day. Meanwhile there is an increase in carbohydrate consumption. This seems to add weight to the link between more carbohydrates and greater weight gain.  http://onlinelibrary.wiley.com/doi/10.1002/osp4.23/pdf

What does this mean?

The studies are not all pointing in the same direction, however there are some compelling research articles suggesting that low carbohydrate diets cause more weight loss than low fat diets. It also appears your effort in sticking to a low carbohydrate diet will pay off more than effort in a low fat diet. As it is not a consensus among studies, it is still good to be cautious but if you are after a diet it looks like cutting down on carbs is a good thing. This is not a license to go crazy consuming copious amounts of fat, and vitamins, fiber and minerals would still be vital.

Additionally, and critically, there may be some side-effects of the diet including increased cholesterol. A doctor’s advice should be sought out on an appropriate diet for yourself. https://www.cambridge.org/core/journals/british-journal-of-nutrition/article/effects-of-low-carbohydrate-diets-v-low-fat-diets-on-body-weight-and-cardiovascular-risk-factors-a-meta-analysis-of-randomised-controlled-trials/B8FBAC51C156D8CAB189CF0B14FB2A46