Some people can eat breads, pastas, rice and potatoes without any negative effect. I envy the people who lost weight just counting calories (no matter the source) and exercising. For me, it wasn't enough.

While I was in Spain and France, I noted slim and healthy locals eating breads and pastries. In Korea, cups of rice were consumed with every meal. A person with no issue eating these foods might conclude these populations don't have weight issues with carbs, therefore there is no issue with carbs.

This is erroneous. These populations never gained excessive weight they had to lose in the first place.

From my personal anecdotal experience, eating a low to moderate amount of carbs in maintenance is not an issue. However, if I want to spur weight loss, then I need to cut it back.

I gained about 5lbs over the holidays eating breads, stuffing, and baked goods. To lose it, I stopped eating them. I ate only protein and veg.

Like many people, as a kid I could mostly eat whatever I wanted without too much thought about it. There was certainly a genetic factor, but what tipped me over the threshold was a period of metabolic abuse. I consumed excessive amounts of sugary sodas, margaritas, potato chips, french fries, hamburger buns, pastas, and desserts. Excessive amounts of sugar is toxic to cells. Insulin receptors become less sensitive, shut down or die. All cells become less sensitive as they age, but sugar overload accelerates it. Once you lose insulin sensitivity, it is gone forever. The damage is permanent.

The insulin receptors that go dormant can be revitalized with exercise and diet, but the damaged ones will never come back. If this gets bad enough, it eventually becomes pre-diabetes or diabetes.

The more insulin sensitivity you lose, the harder it is to lose weight and keep it off. This is a factor in why some people seem to have more or less problems with carbs than others. Some people will be able to resume eating a small amount of carbs after they reach their weight goals. Others have to eat lower amounts forever. It depends on the amount of cumulative damage.

I did enough damage that I cannot lose weight without cutting carbs, but I maintain ok. Personally, I cannot stay very low carb for a long period of time. There are drawbacks to a high carb diet that no one tells you about, and I'm not going to be one of those people who says there are none on low carb, either. Constipation and a potassium drop are two issues I get with long term low carb. I've found that carb cycling where I eat more amounts of sweet potatoes, rice, potatoes or fruit, then drop them off at intervals works best for me.

I will never again be able to eat as much pizza, burgers, soda or margaritas as I did in my 20s, but would I really want to? How much better off would I have been if I just ate unprocessed meats and veggies to begin with? Maybe I should have spent less time making fun of health nuts and joined them. I became one eventually anyway, and found I liked it.