Dairy and keto go together so naturally that for many people butter, cheese and cream become the backbone of the diet. For others, dairy quietly stalls their progress or upsets their skin or gut. Both can be true, which is why dairy deserves a clear-eyed look rather than blanket endorsement. Here is what fits, what to watch, and how to do keto well if dairy does not suit you.
Why dairy suits keto
Full-fat dairy is a near-ideal keto food: high in fat, reasonable in protein, low in carbohydrate, satisfying, and endlessly useful in cooking. Butter, hard cheeses, double cream, full-fat Greek yoghurt and cream cheese are all low in carbohydrate and easy to build meals and snacks around. Cheese in particular is a convenient, portable keto staple, and a splash of cream turns a sauce or coffee rich without carbohydrate. For people who tolerate it well, dairy makes keto more pleasant and more sustainable.
The carb traps to watch
Not all dairy is low-carb, because dairy contains a natural sugar, lactose. The rule of thumb is that the more liquid and less fermented or aged the dairy, the more sugar it carries. Milk is surprisingly carby and easy to overdo in coffee and tea; sweetened and fruit yoghurts can be loaded with sugar; and low-fat dairy often has more carbohydrate than full-fat, because removing the fat leaves the sugars more concentrated and sometimes adds them back for flavour. Hard aged cheeses, butter and cream, by contrast, are very low in carbohydrate because the lactose has largely been removed or fermented away. So choose full-fat, aged and unsweetened, and watch milk and sweet yoghurts.
When dairy is the problem
Here is the part worth knowing if your keto is not going to plan. In some people dairy causes trouble even when the carbs are accounted for. It can stall weight loss, because dairy protein is quite insulinogenic for some individuals, prompting more of an insulin response than expected. It can trigger cravings and overeating, since cheese is very easy to keep nibbling. And in sensitive people it can aggravate acne, cause bloating and digestive upset, or contribute to inflammation. Lactose intolerance is common too. So if you have hit a plateau, or your skin or gut has worsened on keto, dairy is one of the first things worth suspecting.
How to tell if it is you
The simplest test is to cut dairy out for two to three weeks and see what happens. If a stubborn plateau breaks, your skin clears, or your bloating settles, you have your answer, and you can either keep dairy out or reintroduce it in smaller amounts to find your tolerance. If nothing changes, dairy is fine for you and you can enjoy it. This kind of short, deliberate elimination is far more informative than guessing, and it costs you nothing but a couple of weeks.
Doing keto dairy-free
Keto works perfectly well without any dairy, which is reassuring for the lactose-intolerant, the dairy-sensitive and anyone avoiding it. For fats, lean on olive oil, avocado and avocado oil, coconut oil, nuts, seeds and tahini rather than butter and cheese. For creaminess, full-fat coconut milk and cream stand in for dairy cream in cooking, and unsweetened almond or coconut milk replaces milk in drinks. The dairy-free “cheese” substitutes are mostly disappointing and often starchy, so rather than chase a cheese replacement, build meals around whole foods that never needed it. And get your calcium from non-dairy sources such as leafy greens, tinned sardines with their bones, almonds and seeds, so cutting dairy does not cost you the nutrient it is best known for.
The bottom line
Dairy is a genuinely good keto food for those who tolerate it, as long as you choose full-fat, aged and unsweetened and watch the lactose in milk and sweet yoghurts. But it is also a common hidden culprit behind stalls, cravings, acne and gut upset, so if your keto is not working as expected, try cutting it for a fortnight and see. And if dairy does not suit you, keto is entirely doable without it, using plant and other fats, coconut for creaminess, and non-dairy calcium sources. Use dairy if it serves you, drop it if it does not, and the diet works either way.
This is general information about the ketogenic diet, not medical advice. If you are pregnant, on medication, or managing a condition, speak to a doctor or dietitian before changing your diet.