“Humans are not supposed to drink milk after infancy.”
Strong confidence because many human populations evolved lactase persistence, which allows lactose digestion in adulthood, and human outcome research does not show that milk is broadly harmful after infancy. Milk is optional, and tolerance varies.
Many adults can digest milk because lactase persistence is a normal human genetic trait. Other adults digest less lactose and may feel better with smaller amounts, lactose-free milk or fermented dairy. Neither group proves what every human should eat.
Humans also use cooking, fermentation and food processing to expand what we can eat. Evolution is not a rule that foods introduced after infancy or agriculture are unhealthy.
Lactose intolerance can cause gas, bloating, pain or diarrhea. Milk allergy is a different immune condition and requires stricter avoidance.
Can milk support a healthy diet?
Yes. Milk can provide protein, calcium, vitamin B12 and other nutrients. The same nutrients can also come from other foods or fortified alternatives.
Safety note: Milk allergy can cause serious reactions and is not the same as lactose intolerance. Unpasteurized milk carries infection risk.
Talk to a healthcare professional if: Discuss persistent digestive symptoms, poor growth, nutrient concerns or possible milk allergy with a qualified clinician.
You do not need to drink milk, but you also do not need to avoid it because humans are mammals. Use your tolerance, preferences and nutrition needs.
If regular milk bothers you, try a smaller serving, lactose-free milk or yogurt before assuming all dairy is harmful.