Why do i get headache after every meal?

Try smaller meals: There is no good answer, however, it would be worthwhile reducing the size of the servings. For good health - Have a diet rich in fresh vegetables, fruits, whole grains, low fat milk and milk products, nuts, beans, legumes, lentils and small amounts of lean meats. Avoid saturated fats. Exercise at least 150 minutes/week and increase the intensity of exercise gradually. Do not use tobacco, alcohol, weed or street drugs in any form. Practice safe sex.

Many things: If it is with certain types of foods it may be the sodium content (salt) causing blood pressure changes, blood sugar changes (either hyperglycemia - diabete or pre diabetes - or reactive hypoglycemia, a migraine variant, some people get headaches from some food additives, this is common with alcohol, then there are much more rare things. Start by keeping diary of what you ate prior each headache.