Hi, I am Dr.Shreyash Mehta, MD Community Medicine
I understood your query, I hope my answer shall solve your query
As you told that your physical activity is more. So of course your energy requirement will be more.
You are about 10 kg less than average weight for your height.
It may be possible that your
basal metabolic rate may be high.
If you have complaint of loose stools may must get yourself examined by the doctor to rule out
malabsorption syndrome.
If there is no such complaint then
I would suggest you to take in your breakfast, complex carbohydrates like food containing whole grains like whole grain bread/porridge. You can add milk, egg and cheese to your diet. This complex carbohydrates, egg, cheese will stay in your stomach for longer time and you will feel less hungry.
You can increase the amount of complex carbohydrate in your lunch like increasing amount of whole grain bread/rice. You can add pulses/ white meat if possible.
In the dinner also you can add the food with higher complex carbohydrate content like whole grain bread/rice, porridge and white meat
If this diet does not help then you must get yourself examined by physician.