People on the keto diet need to get 55%–60% of their daily calories from fat in order to stay in ketosis. This means that a person consuming 2,000 calories per day needs approximately 122–133 grams (g) of fat daily.
The Dietary Guidelines for Americans 2015–2020 recommend limiting sources of saturated fat, such as red meat, butter, and dairy, due to their links with heart disease.
However, a 2016 meta-analysis indicates that butter has only a small association with mortality, cardiovascular disease, and diabetes.
What is clear is that unsaturated fat has a positive impact on health. In 2016, researchers investigated a large population study that had followed people for three decades. They found that consuming higher amounts of unsaturated fat was associated with a lower risk of mortality.
According to Harvard School of Health, foods that contain unsaturated fat include:
- avocados and avocado oil
- nuts, such as walnuts, macadamias, almonds, and Brazil nuts
- seeds, such as flax and pumpkin seeds
- oily fish, such as salmon, tuna, anchovies, and sardines
- olives and olive oil
These are all healthful sources of fat for people following the keto diet.
Despite being a source of saturated fat, coconut oil also has some health benefits. A 2018 study showed that coconut oil increased high-density lipoprotein (HDL), or good, cholesterol compared to olive oil and butter. This type of cholesterol can protect against heart disease.