If you've been following my "weight loss" series (Why bother? and Why is it so hard?), I've now got to the point where I'm going to be even more blunt and opinionated.
When it comes to the matter of body weight/fat there are two types of people; people who have a metabolic/endocrine problem and people who don't. I previously thought the former group was vanishingly small, but I've been reading and learning a lot and I've changed my mind. People with genetic, pre-existing endocrine problems -are- rare; people with acquired metabolic problems are pretty common and it's usually varying degrees of insulin sensitivity from the sensitive to bordering on type II diabetes and mainly due to battering the body with high levels of (refined) carbohydrates until it starts to give up. Some bodies are more susceptible than others to running into problems with this. Some take a long time to show any effects. Some never have a problem at all.
Gary Taubes, Tim Noakes, Steven Phinney, Jeff Volek, Peter Attia, Aseem Malhotra, Yoni Freedhoff and many others have researched, thought, read, and digested (pun intended) on the topic and have come to the conclusion that the modern obesity pandemic is caused by cheap, freely available, highly processed, large amounts of carbohydrates in the human diet. Not just Western society; but increasingly across the whole of the world and as the availability of cheap, highly processed carbs increases, any given country will see an increase in obesity, diabetes and a number of other chronic diseases.
If you put on weight quite easily, are slowly gaining weight as you get older, have a high waist-to-hip ratio, struggle to lose weight or maintain healthy weight, crave foods, get hungry a lot of the time, think about food a lot (in terms of when/where is your next meal coming, or how you can justify eating X or Y, not in terms of a recipe you'd like to try 'cause it looks interesting or it's your job etc.) you are probably along the path to insulin insensitivity/resistance. If that is the case, you would probably benefit from a low carbohydrate diet for general health reasons and a side-effect of a low carbohydrate diet could well be weight loss. When I say "diet" here, I do not mean it in the sense of "going on a...", I mean it in the sense of what you eat for now and forever.
If you don't put on weight easily, have a relatively healthy waist-to-hip ratio, don't vary much in body weight with time, have no problem losing a few pounds (maybe for the racing season?), don't get food cravings, don't have "intrusive thoughts of food", then you're probably towards the "no problem" end of the insulin sensitivity scale. You're quite lucky. Also, a low carbohydrate diet will probably have little effect on your weight. That said, there are a good few reasons why you might want to move to a higher fat (and, logically, lower carb) diet (have a read of Why We Get Fat and what to do about it and/or The Great Cholesterol Con). I don't mean to the extent of this...
...but golly-gosh there are a lot of good things in some of them thar fats like olive oil, avocado oil, coconut oil, beef fat (grass fed), salmon (wild), mackerel, herring, butter and milk (grass fed), eggs (free range, organic), macadamia nuts, brazil nuts etc.
So if you are away from the lucky end of the insulin sensitivity scale and want to change, take a look at your diet. See how much white flour, potatoes, sugar, white rice etc. you eat, or even how much brown rice, brown flour, brown pasta, bananas, fruit juices etc. if it's more than 200g or so per day. If you are struggling to lose weight, suffer unpleasant hunger/cravings, can't make it work on a calorie counting diet (usually low fat), CHANGE THE STRATEGY. Swap low fat for low carb. Eat real butter, milk, cheese, eggs, meat, fish and feel less hunger. If you go low enough carb for a few days you'll stop getting cravings, stop the constant thinking about food, stop the horrible hunger sensations. You'll enjoy what you're eating! You'll start to find that things like strawberries are insanely sweet-tasting without adding sugar because you can actually taste them properly. You'll start to find that you don't need a huge plate piled high with pasta, rice, potatoes, bread etc. to feel satisfied after a meal.
And if you think it's all too much like hard work, there are so many quick and easy things you can make/cook/grab on the go. And if you think low carb is too restrictive and all you'll be eating is bacon and eggs... well, there's a lot of help and ideas and once you get going it's really really easy.
And it's a change for life.