01/30/2026
Dairy and Acne: Why Humans Struggle to Digest Milk After Childhood (doesn’t matter raw milk/goat milk etc)
Human bodies are biologically designed to drink breast milk in infancy, not animal milk long-term.
After around age 5–12, most humans naturally reduce production of an enzyme called lactase, which is required to break down lactose (the sugar in milk). This is known as lactase non-persistence, and it’s the global norm—not a disorder.
Without enough lactase,
lactose ferments in the gut and causes bloating, gas, cramps, acne, inflammation, or diarrhea. It disrupts gut microbiome balance.
Evolutionary reality: Humans are the only species that drinks another animal’s milk—and the only ones who do it past weaning.
Inflammatory response: Dairy proteins (casein & whey) can trigger low-grade inflammation, mucus production, sinus issues, and skin flare-ups in many adults. Milk causes spikes in blood sugar, which, in turn, triggers the bodies inflammation response. These same spikes trigger increased production of pore-clogging sebum (oil) and change the composition of that sebum. Skim and low-fat milk have a higher glycemic index (GI), which causes blood sugar spikes that stimulate insulin secretion, leading to increased oil production.
Gut health impact: Undigested lactose feeds harmful gut bacteria and yeast, leading to digestive distress and systemic symptoms.
Hormonal influence: Cow’s milk contains natural growth hormones meant for calves, not humans, which may interfere with hormonal balance in sensitive individuals. Even dairy products labelled hormone-free still contain over 60 naturally occurring hormones that humans don’t need, as we are not baby cows.
So what does all of that mean? If milk causes discomfort, skin issues, fatigue, or inflammation, it’s not “normal” aging—it’s your body signaling a mismatch.
Fermented options (like kefir or yogurt), plant-based alternatives, or removing dairy altogether often lead to improved digestion, clearer skin, and better energy.
