Dairy and gluten: test them for 30 days instead of guessing
“I have an intolerance” is most often said based on an IgG test result, which proves nothing, or an article on the internet. There is a more honest and cheaper way: eliminate it for 30 days, reintroduce it for three, and record the results. Your body will answer more accurately than any laboratory. Section — microbiome and intolerances.
Dairy: lactose and casein are not the same thing
Lactose is milk sugar. The lactase enzyme declines with age in most adults, and a glass of milk causes bloating and diarrhea within an hour or two. At the same time, hard cheeses, butter, cream, and kefir contain little or no lactose — they are tolerated. Casein is a milk protein; reactions to it are less common, but they affect all dairy products, including cheese and butter: skin, mucus, joints, fatigue. The distinction is simple: if cheese and butter are fine but milk is not, it is lactose. If all dairy products cause problems, it is casein.
Dairy with lactase deficiency
| Product | Lactose | Tolerance |
|---|---|---|
| Milk | 5 g per 100 ml | poor |
| 30% cream | 3 g per 100 ml | a spoonful in coffee — usually fine |
| Kefir, plain yogurt | 2-3 g per 100 ml | often fine — bacteria have consumed some of it |
| Cottage cheese | 1-2 g per 100 g | varies |
| Hard cheese | 0-0.1 g | good |
| Butter | traces | good |
| Lactose-free milk | 0 | fine, but the sugar is the same |
Gluten: it is absent from the method, and that is the test
Wheat, rye, and barley disappear on a low-carb diet along with flour. After a month, many people notice that their stomach is calmer, their skin is clearer, and their joints feel better — without knowing whether it was sugar or gluten. Reintroduction provides the answer: two slices of bread for three days in a row. If you develop bloating, brain fog, joint pain, or skin symptoms, gluten is your trigger. If nothing happens, it was the sugar, and bread simply is not needed for another reason. Celiac disease is a separate matter: antibody testing must be done BEFORE eliminating gluten, otherwise the result may be falsely negative.
The 30/3 protocol
Choose one product
Dairy or gluten — not both at once. Otherwise you will not know.
30 days without it, completely
Including hidden sources: cheese in sauces, milk in coffee, soy sauce with wheat, breading.
Note it every day
Stomach, bowel movements, skin, sleep, joints, energy — on a scale of 1-5.
Reintroduce for 3 days
A regular serving every day. The same notes.
Compare and decide
Worse — intolerance is present; eliminate the product or keep it at the dose you tolerate. No difference — bring the product back.
What does not count as a test
An IgG test for foods shows that you have eaten the food, not that it is harmful; medical societies do not recommend it. “I feel that dairy does not agree with me” without 30 days of elimination is not a test. Giving up everything at once “just in case” impoverishes your diet without providing an answer. About bloating, which has many causes besides intolerance, see bloating.
Frequently asked questions
Where do I get calcium without dairy?
Sardines with bones, sesame, almonds, broccoli, leafy greens. And hard cheese if the problem is lactose, not casein.
Goat’s milk with an intolerance?
It contains the same amount of lactose. The casein is a different type, which is easier for some people. The test is the same: 30 days and reintroduction.
Is gluten harmful to everyone?
No. Celiac disease affects 1%, and sensitivity affects several percent. For the rest, bread is unnecessary because of flour and sugar, not gluten.
- Digestion When You Change Your Diet
- Heartburn, Gallbladder, Sensitive Gut
- Microbiome and Intolerances
Reviewed by Anastasia Zhukova, Fitness Trainer • Author of a Nutrition and Training System • Creator of an AI Personal Support Platform
A human has reviewed this material against the method and real client practice.