"Bad" cholesterol, "good" cholesterol, total cholesterol, triglycerides, HDL/LDL ratio — your cholesterol panel can feel like an alphabet soup. But heart disease remains the UK's biggest killer, responsible for around 1 in 4 deaths according to the British Heart Foundation. Understanding your cholesterol numbers is one of the highest-leverage things you can do for long-term health.
What is cholesterol?
Cholesterol isn't a poison — it's a fat-like substance your body actually needs. Every cell membrane uses it. Vitamin D, bile, and steroid hormones (including testosterone and oestrogen) are all built from it. Around 75% of the cholesterol in your body is made by your liver. Only 25% comes from food.
The reason cholesterol gets a bad reputation is that it travels through your bloodstream packaged in lipoproteins — and the type of packaging matters more than the cholesterol itself. That's where LDL and HDL come in.
LDL vs HDL — what's the difference?
LDL (Low-Density Lipoprotein) — often called "bad" cholesterol. LDL particles deliver cholesterol to your tissues. When there are too many, especially small dense LDL particles, they can lodge in artery walls and contribute to plaque buildup.
HDL (High-Density Lipoprotein) — often called "good" cholesterol. HDL particles collect cholesterol from your tissues and return it to the liver for processing. Higher HDL is generally protective.
So a healthy cholesterol profile isn't just about total cholesterol — it's about the balance: enough HDL, controlled LDL, and (often most importantly) low triglycerides.
What do the numbers mean?
UK reference ranges (in mmol/L):
- Total Cholesterol: Aim for below 5.0 mmol/L. Below 4.0 if you have heart disease risk factors.
- LDL Cholesterol: Below 3.0 mmol/L (below 2.0 if high risk)
- HDL Cholesterol: Above 1.0 (men) / Above 1.2 (women)
- Triglycerides: Below 1.7 mmol/L (fasting)
- Total/HDL Ratio: Below 4.0 (lower is better)
The Total/HDL ratio is one of the most useful single numbers in a cholesterol panel — it captures the balance between protective and risky particles in one figure. A ratio of 3.0 or below is excellent. Above 5.0 raises concern.
Three things you might not know about cholesterol
1. Triglycerides may matter more than LDL
For people with metabolic syndrome, prediabetes, or insulin resistance, elevated triglycerides are often a stronger predictor of heart disease risk than LDL. High triglycerides usually point to dietary sugar and refined carbohydrate intake — not dietary fat. Reducing sugar typically lowers triglycerides faster than reducing fat lowers LDL.
2. Dietary cholesterol has surprisingly little effect
For decades, eggs were demonised. The science has moved on: dietary cholesterol (from eggs, shellfish) has a relatively small impact on blood cholesterol for most people. Saturated fats and refined carbohydrates affect blood cholesterol more directly. Most current UK guidelines no longer cap egg consumption.
3. Exercise barely changes LDL but dramatically raises HDL
Aerobic exercise — particularly moderate-intensity continuous training — is one of the most effective ways to raise HDL. It does relatively little to LDL on its own. Combined with dietary change, it shifts the whole profile.
What raises and lowers cholesterol naturally?
Lowers LDL / raises HDL:
- Soluble fibre (oats, beans, apples, psyllium)
- Olive oil and oily fish (omega-3s)
- Nuts, particularly almonds and walnuts
- Regular aerobic exercise
- Maintaining a healthy weight
- Quitting smoking
Raises LDL / lowers HDL:
- Trans fats (industrial baked goods)
- Refined sugar and ultra-processed foods
- Sedentary lifestyle
- Excess alcohol
- Chronic stress and poor sleep
How to test your cholesterol
Cholesterol is included in our Lipid Health panel — covering Total Cholesterol, LDL, HDL, Triglycerides, and the Total/HDL ratio. It's also bundled into broader screens like Heart Health, Standard Screen, and Metabolic Syndrome.
For most accurate results, test in the morning after a 9-12 hour fast (water only). Visit our County Durham clinic or a UK partner clinic — results in 3-5 working days as a clear PDF report.
Browse our heart and metabolic panels →
This article is informational. Chxhealth is a biomarker and genetic data provider — we do not diagnose, treat or prescribe. If your results are outside typical ranges, talk to your GP or a healthcare professional about next steps.
