On a keto diet, most people consume 20-50 grams of net carbs daily to stay in ketosis. This strict limit forces your body to burn fat for fuel instead of glucose.
Ketosis occurs when your body lacks glucose (from carbs) and starts breaking down stored fat into molecules called ketones. These ketones become your primary energy source.
The liver converts fat into ketones only when carb intake is very low. Most people enter ketosis eating fewer than 50 grams of net carbs per day.
Not all carbs count equally. The keto diet focuses on net carbs-total carbs minus fiber and sugar alcohols, which don't raise blood sugar.
| Carb Type | Counts Toward Net Carbs? |
|---|---|
| Fiber | No |
| Sugar alcohols | Partially (about half) |
| Starch | Yes |
| Sugars | Yes |
Many people confuse total carbs with net carbs. For example, a cup of cooked broccoli has 6 grams of total carbs but only 4 grams of net carbs due to its high fiber content.
Some keto diets allow up to 50 grams of net carbs, while others restrict to 20 grams. The lower end is stricter and may lead to faster weight loss.
Many beginners underestimate hidden carbs in sauces, drinks, and processed foods. A tablespoon of ketchup, for instance, contains about 4 grams of net carbs.
I once saw a client struggle with weight loss on keto until we discovered their morning coffee had 15 grams of carbs from flavored creamer.
To find net carbs, subtract fiber and (optionally) half of sugar alcohols from total carbs. For example:
Total carbs: 10g Fiber: 3g Sugar alcohols: 2g Net carbs = 10g - 3g - (2g / 2) = 7g
Some people need fewer carbs to stay in ketosis, especially athletes or those with insulin resistance. Others may tolerate slightly more carbs without kicking themselves out of ketosis.
The best way to know your personal limit is to test your ketone levels using urine strips or a blood ketone meter.