How much fat should you eat on low carb or keto?

Are you hungry? Don’t be. When you start a low-carb diet and cut back on carbohydrates, the trick is to eat enough protein and fibrous veggies, and then fuel your remaining energy needs with fat.1

How much fat should you eat? It’s not a very exciting answer, but the real answer is, “It depends.”

Although we have essential fatty acids that we need to eat, we don’t have a pre-defined amount of fat we should eat like we do with protein.2 That is why our three rules of low-carb eating are:

  1. Reduce carbohydrate to the desired level
  2. Get adequate protein at nearly every meal
  3. Use fat as needed for flavor and, if needed, extra calories

Fat — either from our food or from our fat stores – supplies those extra calories and extra energy that we used to get from carbs. You should eat enough fat to enjoy your meals and to stave off hunger between your meals if needed. Shoot for feeling pleasantly satisfied, but not overfed after each meal. After dinner, you should make it easily through the night – 12 hours without hunger (if not more). Work towards finding this balance.

Below are a few refinements to this advice, if you really want to maximize the effectiveness of your low-carb diet.

Key takeaways


1. Don’t fear fat

For decades we have heard the message that we should reduce the amount of fat in our diets.3 In terms of scientific evidence, links between saturated fat and heart disease are weak and inconsistent.

Although some reviews of the literature do find a weak relationship, an increasing number of meta-analyses and systematic reviews find that there is no significant connection between saturated fat and heart disease.4

However, the lingering fear of fat may remain for many people. Step one to getting the right amount of fat for you is to move past any fear that eating fat makes us fat, or that eating fat is automatically bad for our health.

You can learn more in our guides on healthy fats, saturated fat, and 10 ways to eat more fat.

2. Ease into fat adaption

When you begin your low-carb journey, you may find some high-fat foods taste ‘too rich.’ Be patient. As you transition to your new way of eating, both your body and your taste buds will adjust.5 Work up to eating enough fat to avoid hunger and allow your body time (at least a month) to settle into its new pattern of burning fat instead of carbohydrates.

You will likely reach a point where your hunger will diminish. This is when you may want to back off on the amount of fat you eat so you can prioritize burning your body fat stores instead.

3. Dial back for weight loss

Hoping to lose weight? If the answer is yes, once you are at ease with your low-carb diet, experiment with reducing the extra fat you add to meals.

Eat just enough to enjoy your food – let your body burn its internal fat stores rather than that extra pat of butter. This will likely accelerate weight loss.6

But don’t go too far – when hungry, always opt for additional protein and fiber-filled veggies first, followed by extra fat if needed, rather than deviating from your low-carb plan.

4. Add fat as needed for maintenance

Once you reach your goal weight, you may no longer have the internal fat stores necessary to fuel an energy shortfall day after day. Tune into your body’s hunger signals. Now is the time to gradually adjust the fat in your diet until you find the satisfying balance of hunger-free weight maintenance.

5. Eat an adequate amount of protein

The most helpful trick to minimizing hunger is making sure you eat the right amount of protein. If you are eating very low-carb but have stalled with weight loss, or if you find yourself hungry between meals, take a look at how much protein you are eating.

How much is enough? Individual needs vary, but about 1.2-2.0 grams of protein per kilogram of reference bodyweight (each day) may be optimal for weight loss.7 You may need more if you are active, especially if lifting weights and trying to build muscle.8

Learn more about protein on a low-carb or keto diet


  1. Just because you can eat more fat for fuel, doesn’t automatically mean that you will. In studies where people are eating low-carb, moderate-protein diets and are allowed to eat as much fat as needed to feel full, they often end up consuming less overall due to feeling fuller and more satisfied:

    Nutrition & Diabetes 2017: Twelve-month outcomes of a randomized trial of a moderate-carbohydrate versus very low-carbohydrate diet in overweight adults with type 2 diabetes mellitus or prediabetes [moderate evidence]

    Annals of Internal Medicine 2005: Effect of a low-carbohydrate diet on appetite, blood glucose levels, and insulin resistance in obese patients with type 2 diabetes [non-randomized trial; weak evidence]

    Nutrition & Metabolism 2005: A low-carbohydrate, ketogenic diet to treat type 2 diabetes [non-randomized trial; weak evidence]

  2. Journal of Dietary Supplements 2009: The essentials of essential fatty acids [overview article; ungraded]

  3. Circulation: 2013 AHA/ACC guideline on lifestyle management to reduce cardiovascular risk: A report of the American College of Cardiology/American Heart Association task force on practice guidelines [consensus guidelines; ungraded]

  4. Here are four meta-analyses showing no connection between saturated fats and heart disease:

    When looking at RCTs, this review found no relationship between saturated fat and heart disease, though it did find a relationship when looking at observational studies.

    Annals of Internal Medicine 2009: Dietary fat and coronary heart disease: Summary of evidence from prospective cohort and randomized controlled trials [moderate evidence]

    A 2020 Cochrane review of RCTs showed a modest reduction in cardiovascular events for lower saturated fat intake. But it found no benefit to lowering saturated fat intake for heart attack, stroke, cardiovascular death, or all-cause death.

    Cochrane Database of Systemic Reviews 2020: Reduction in saturated fat intake for cardiovascular disease [systematic review of randomized trials; strong evidence]

    Learn more about the science of saturated fat

  5. This is based on consistent clinical experience of low-carb practitioners. [weak evidence]

  6. This is based on consistent clinical experience of low-carb practitioners. [weak evidence]

  7. British Journal of Nutrition 2020: The effect of 12 weeks of euenergetic high-protein diet in regulating appetite and body composition of women with normal-weight obesity: A randomised controlled trial [randomized trial; moderate evidence]

    American Journal of Clinical Nutrition 2015: The role of protein in weight loss and maintenance [overview article; ungraded]

    The Journal of Nutrition 2013: Normal protein intake is required for body weight loss and weight maintenance, and elevated protein intake for additional preservation of resting energy expenditure and fat free mass [randomized trial; moderate evidence]

  8. Nutrients 2018: Effects of a high-protein diet including whole eggs on muscle composition and indices of cardiometabolic health and systemic inflammation in older adults with overweight or obesity: a randomized controlled trial [moderate evidence]

    The American Journal of Clinical Nutrition 2017: The effects of dietary protein intake on appendicular lean mass and muscle function in elderly men: a 10-wk randomized controlled trial [moderate evidence]