Keto and Cholesterol: What Happens to Your Lipids, and What to Do
For many people keto improves triglycerides and HDL. For some, LDL rises, sometimes a lot. The only way to know which group you are in is a blood test.
Short answer: It depends on the person. Triglycerides often fall and HDL often rises on keto, but LDL cholesterol rises in some people, occasionally sharply. Test your lipids before starting and after about three months, and review the results with your doctor.
What usually changes
Lipid changes on a ketogenic diet vary a lot between people. The pattern commonly reported is:
| Marker | Common direction on keto | Why it matters |
|---|---|---|
| Triglycerides | Often fall | Lower carbohydrate intake, especially sugar, is a strong driver |
| HDL ("good") cholesterol | Often rises | Higher fat intake and weight loss both tend to raise it |
| LDL ("bad") cholesterol | Varies. Unchanged in some people, raised in others | Saturated fat intake, genetics and body size all play a part |
A minority of people see a large LDL rise on keto. It is more often reported in lean, active people and in diets very high in butter, cream and fatty red meat. Because LDL is a well-established risk factor for heart disease, a large rise is worth taking seriously, not explaining away.
Test, don't guess
- Get a baseline lipid panel before starting, if you can: total cholesterol, LDL, HDL and triglycerides.
- Repeat it after about three months on keto, ideally under the same conditions (same time of day, same fasting state).
- Retest about three months after any change you make to your fat sources.
- Discuss the results with your doctor, especially if LDL has risen markedly. It is a conversation about your overall risk, not just one number.
If your LDL goes up
These changes keep the diet keto while shifting the fat profile:
- Swap saturated for unsaturated fat: olive oil and avocado instead of butter and cream for most cooking and dressings.
- Eat oily fish like salmon, sardines or mackerel two to three times a week.
- Add nuts and seeds: walnuts, macadamias, chia and flax.
- Raise fibre with low-carb vegetables every day. Soluble fibre from flax and chia helps.
- Cut back on processed meats and "fat bombs" made mostly of butter or coconut oil.
- Consider a looser low-carb plan (50–100 g) if LDL stays high. See keto vs low carb.
Who should talk to a doctor before starting
- People with familial hypercholesterolaemia or a known very high LDL
- Anyone with existing heart disease, a previous heart attack or stroke, or a strong family history of early heart disease
- People taking cholesterol-lowering medication, who may need monitoring rather than stopping it
More on who needs supervision in is the keto diet safe?
Frequently asked questions
Is a keto diet bad for cholesterol?
It depends on the person. Triglycerides often fall and HDL often rises on keto, but LDL cholesterol rises in some people, occasionally sharply. Test your lipids before starting and after about three months, and review the results with your doctor.
Why does LDL go up on keto?
The most common reason is a high intake of saturated fat from butter, cream, coconut oil and fatty red meat. Genetics and body size also play a part. Lean, active people seem more likely to see a large rise.
How can I lower cholesterol on keto?
Shift fat sources towards olive oil, avocado, nuts, seeds and oily fish, eat more low-carb vegetables for fibre, and cut back on butter-heavy foods and processed meats. Retest after about three months.
This guide is general information for healthy adults, not medical advice. See our medical disclaimer.