Macros & Common Problems
Macronutrients are broken down into 3 subcategories (protein, carbs and fats). When these are all added up they make up the amount of calories you have consumed. The ratio of these macros will also dictate hormone type and function. For example consume too many carbs produce a lot of insulin.
So what problem does the average person face?
1) Eating TOO much overall
When the main goal is to lose weight you need to create a calorie deficit. This can be achieved through nutrition by consuming less food or by increasing activity.
2) Non specific ratio of macros
Some people are genetically able to handle carbohydrates better than others and will work better with a higher ratio of carbs in their macro breakdown. However some would benefit from decreasing(not completely removing) carbs and therefore increasing sensitivity to insulin.
For those who enjoy a diet higher in fats, medium protein and lower carbs a ketogenic diet would be suitable.
Choose a diet which you can consistently follow, there are tons of diets to choose from and they all have one commonality. They all require a calorie deficit to lose weight or calorie surplus to gain weight.
3) Eating too little
By going to the other extreme and limiting calories especially below your BMR for too long can lead to metabolic damage or adrenal fatigue (other factors also come into play). Your metabolism will slow down in order to adjust to new baseline calories. People who see very fast but short lived results usually suffer from some form of metabolic damage. They eat very low calories, lose weight, their metabolism adjusts and their calories stay the same. This leads to weight gain as metabolism has down regulated and needs less to run your body (technically in a calorie surplus now).
4) Doing too much too quick
This ties in to the above point. By drastically increasing activity levels and not compensating through nutrition you put yourself at risk of adrenal fatigue. Does this sound familiar? You exercise loads racking up the time on the treadmill, cross trainer, bike etc and your calories are low but you're not seeing any results or staying the same. At the start of your weight loss phase you need to do as little as you can to get into a deficit and increase activity levels slowly as your body adjusts.