How can I improve my tendency to gain weight and maintain a low body fat percentage? 

Is there such a thing as a fat-prone constitution? Fat people often say that they gain weight even when they drink water or breathe air, while thin people often say that fat people gain weight because they can't control their appetites. Is there such a thing as being born prone to weight gain? 

According to research, obesity is very closely related to genetic predisposition. A relatively big difference is the level of hormones people are born with. For example, some people are born with problems with insulin secretion, so they tend to gain weight when they eat carbohydrates. Or they may have problems with hormones that control the feeling of fullness, so they don't feel full easily, get hungry easily, and are easily tempted by food. These things make them naturally unable to. Apart from hormonal issues, the body's inflammatory response to different foods or metabolic efficiency is different. For example, some people will have an intolerance to certain foods, which in turn puts the body in a state of chronic inflammation, greatly increasing the chances of obesity. However, it does not mean that if you are born with a predisposition to obesity, you are doomed to be fat because the acquired environment also has a great influence. 

Acquired causes make your body prone to fat. 
Similarly, it does not mean that if you are born thin, you will always be thin because many acquired causes make your body prone to fat. The first situation that makes you prone to fat is your body's tolerance for various major nutrients. Some people metabolize carbohydrates more slowly, while others are less tolerant of fatty acids. That way, when they eat more fat, they increase their chances of becoming obese. In my experience, most obese people are the former, that is, people who easily gain weight by eating carbohydrates. 
The solution to this problem is very simple. The more obvious one is to reduce carbohydrate intake. Foods high in carbohydrates include starches, roots, fruits, and sweet things. If you really like carbohydrates, eat them around the time of weight training. 
As you can see in the study shared by our nutritionist Zhejun in the figure below, both groups ate high-carbohydrate and high-protein meals. 
Source of the study: https://www.ncbi.nlm.nih.gov/pubmed/27152424 
The first group ate between waking up and going to bed, and the second group ate before and after training. The group that ate before and after exercise and fitness successfully built muscle and lost fat, while the opposite group did not make as much progress 
Another study showed that some people are born with a higher susceptibility to obesity and fatness caused by saturated fatty acids. 
Research source: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3137002/ 
So, when they eat too much saturated fatty acids, they are more likely to become obese. It is just that if you find that you cannot lose weight even though you eat a lot of saturated fatty acids, it is recommended that you eat less saturated fatty acids and more unsaturated fatty acids, such as olive oil. 
The second situation that makes you prone to obesity is chronic inflammation. 
Chronic inflammation in the body can cause fat to accumulate easily and lose muscle mass. Moreover, after fat accumulates, it will further increase the inflammation index. In short, it will make your body prone to obesity. Chronic inflammation can be caused by many things, such as eating too much omega-6 fatty acids, refined carbohydrates, eating too much-fried food, eating foods that you are intolerant or allergic to over a long period, or eating foods that will damage the intestines over a long period. 

According to a book on autoimmune diseases, these foods are more likely to harm the intestines and stomach and can be avoided: Cereals; Gluten; Imitation cereals; Legumes; Dairy products; Beans; Processed vegetable oils; Processed chemicals; Added sugar; Sugar alcohols; Nuts; Nut oils; Seeds; Seed oils; Nightshade; Nightshade-based ingredients; Alcohol; Foods with a high glycemic index. 

Common foods eaten during fat loss include: 

Oats, quinoa, brown rice, chia seeds, various dairy products such as cheese, milk, yogurt, soybeans, soy products, various beans, almonds, cashews, walnuts, and various nuts. Some people are naturally intolerant, allergic to more foods, or have weak stomachs. Then, the ratio of omega-6 to omega-3 fatty acids is also very important. Try to maintain a ratio of omega-6: omega-3 of 3:1, which is not only better for the stomach but also helps with chronic inflammation. 

The problem of satiety 

Some people are born not to feel full when eating, while others like to eat themselves until they are full. 

If you find that you are someone who can easily go hungry or get hungry easily, you can try the following methods: 

Eat more meat, good fats and vegetables 

Because proteins and fiber are the most satiating, and then eat less carbohydrates. Choose foods with a high nutritional density, which simply means eating less processed food and more dark green vegetables and nutrient-rich whole foods. Chew your food slowly. 

Getting a good night's sleep and finding a good way to relieve stress 

The first thing is to sleep and the problem of being prone to obesity. Many people become fatter and fatter as they enter the workplace. A big reason is stress and not getting enough sleep, so they become fatter and fatter. The previous sleep video also talked about not sleeping well, which can affect weight loss by more than 40%. 

This study also shows that the fat loss effect of the group with poor sleep is reduced by 55%, and the muscle loss effect is increased by 60%. 

Source: https://www.ncbi.nlm.nih.gov/pubmed/20921542 

This is mainly because sleep is closely related to hormone secretion in the body. Important hormones such as insulin and growth hormone can be affected by poor sleep. Therefore, it is recommended that you get at least 6.5 hours of sleep. If you have trouble sleeping lightly, try to find a way to solve it. 

The link between eating out and obesity 

In addition to reasons such as food becoming more and more delicious, food portions getting bigger and bigger, and more and more processing, cheap nutritionally void food and expensive nutritious food, etc., there is another very important reason for the problems with eating out: the choice of oil. Most cooking outside the home uses vegetable oils and seed oils, which are mostly Omega-6 six fatty acids, so if you eat out, it is more likely to cause a systemic inflammatory response. This chronic inflammation is just what was said earlier, which makes it easy for the body to gain fat and lose muscle. So the best way is to buy fresh ingredients yourself and use good oil to cook, which is safer. At the same time, avoid eating too much Omega 6, and then supplement with animal Omega 3 to achieve a balance, such as mackerel, salmon, sardines, etc., or supplement with good fish oil supplements. 

The last thing I want to talk about is the problem of weight regain 

After you successfully lose weight, you will be very happy and want to celebrate. But at this time, you will find that you are super prone to weight regain. You will gain weight just by eating whatever you want. This is mainly because the metabolism inevitably decreases during weight loss, and it takes time for the body's internal secretion to adapt to the new weight. So I would suggest that you first maintain a low weight for a while, and if you gain a little weight, you should quickly control it back. Otherwise, it will be very easy to gain weight again.