Can you have heart disease even if you are slim, active and have a normal BMI? Yes. While maintaining a healthy weight can reduce some cardiovascular risks, it does not eliminate them. Cholesterol, blood pressure, genetics, blood sugar, smoking, body fat distribution and other factors can all influence your heart health.
This is why looking healthy on the outside does not always tell the full story about what is happening inside your arteries. In this article, Dr Pinakin V Parekh explains why thin people can still develop heart disease, which warning signs and risk factors to pay attention to, and when a cardiovascular assessment may be worth considering.
Why Being Thin Doesn’t Always Mean a Healthy Heart
Body weight is often used as a quick measure of health, but it is not a complete measure of cardiovascular risk.
One commonly used measure is body mass index (BMI), which uses your height and weight to estimate whether your weight falls within a healthy range.
BMI can be useful, but it has limitations.
It does not tell you:
- How much of your body weight is muscle
- How much is body fat
- Where your body stores fat
- Whether you have high blood pressure
- Whether your cholesterol is elevated
- Whether you have diabetes or insulin resistance
- Whether you have a strong genetic risk for heart disease
This means that someone who looks slim can still have cardiovascular risk factors that are not immediately visible.
Research has also shown that people with a normal BMI can still carry excess abdominal fat, which may be associated with certain cardiovascular and metabolic risk factors. (Source: PubMed Central).
How Can a Slim Person Develop Heart Disease?
Heart disease develops through a combination of factors, and body weight is only one part of the picture. A person can be slim while still having genetic, metabolic or lifestyle-related risk factors that contribute to atherosclerosis.
Genetics Can Increase Your Risk
Some people inherit a tendency towards high cholesterol or other cardiovascular problems. For example, familial hypercholesterolaemia (FH) can cause very high LDL cholesterol from a young age. A person with FH may be slim, active and otherwise appear completely healthy while still having a significantly increased risk of coronary artery disease.
A strong family history of early heart attacks or heart disease can also be an important warning sign, even if you have a normal BMI.
High Cholesterol Can Affect Slim People Too
High cholesterol is not limited to people who are overweight. LDL cholesterol can contribute to the formation of plaque in the arteries regardless of a person’s body size. Genetics, diet and certain medical conditions can all contribute to elevated cholesterol.
This means a slim person with persistently high LDL cholesterol can still develop atherosclerosis, the buildup of plaque in the arteries that can eventually restrict blood flow to the heart.
Smoking, Blood Pressure and Blood Sugar Also Matter
Some cardiovascular risk factors have little to do with how much you weigh. Smoking, high blood pressure and diabetes or impaired blood sugar control can all damage blood vessels and contribute to atherosclerosis.
As a result, someone who appears slim and healthy can still have several underlying risk factors for coronary artery disease. Looking healthy on the outside does not necessarily mean your cardiovascular risk is low.
What About “Skinny Fat”?
You may have heard the term “skinny fat” used to describe someone who looks slim but has a relatively high proportion of body fat, particularly around the abdomen.
While “skinny fat” is not a medical diagnosis, it highlights an important limitation of BMI.
Where fat is stored can matter.
Visceral fat, which accumulates around internal organs, is associated with metabolic problems and cardiovascular risk. Someone can therefore have a normal BMI while carrying more abdominal fat than is ideal.
This is one reason why waist circumference and body composition can sometimes provide additional information beyond weight alone.
What Symptoms Shouldn’t You Ignore?
Being slim should never be a reason to dismiss symptoms that could be related to the heart.
Possible symptoms of cardiovascular disease include:
- Chest pressure, tightness or discomfort
- Breathlessness, particularly if it is new or worsening
- Reduced exercise tolerance
- Palpitations
- Dizziness or light-headedness
- Unusual or unexplained fatigue
Some people with cardiovascular disease may have few or no symptoms, particularly in the earlier stages.
How Is Cardiovascular Risk Assessed?
Rather than asking simply “Am I a healthy weight?”, a cardiologist looks at the bigger picture.
Depending on your age, symptoms and medical history, this may include:
- Blood pressure
- Cholesterol levels
- Blood sugar
- Smoking history
- Family history
- Physical activity
- Waist circumference or body composition
- Symptoms and exercise tolerance
The important point is that not everyone needs every test. A cardiologist uses the patient’s individual risk profile to decide whether further assessment is appropriate.
What Tests Might Be Recommended?
Depending on the situation, assessment may include:
- Blood tests to check cholesterol and blood sugar.
- ECG to assess the heart’s electrical activity.
- Echocardiogram to look at the heart’s structure and function.
- Exercise testing in selected patients to assess how the heart responds to exertion.
- Coronary imaging or other investigations when there is concern about coronary artery disease.
The appropriate test depends on what your doctor is trying to find out. More testing is not necessarily better.
Who Should Consider a Heart Check?
Being slim does not automatically mean you need a heart screening. However, it may be worth discussing your cardiovascular health with a doctor if you have:
- A strong family history of heart disease
- High cholesterol
- High blood pressure
- Diabetes or abnormal blood sugar
- A history of smoking
- Concerning or unexplained symptoms
- A previous abnormal heart test
- Several cardiovascular risk factors
For some people, particularly those with a strong family history or multiple risk factors, a cardiovascular assessment can identify concerns before symptoms develop.
Dr Pinakin’s Approach: Looking Beyond Weight
In clinical practice, Dr Pinakin looks beyond a patient’s weight to understand the factors that may influence their overall cardiovascular risk.
“A patient’s weight is only one part of my assessment. When someone has a normal BMI, I still want to understand their blood pressure, cholesterol, blood sugar, family history, lifestyle and any symptoms they may have. The important question is not simply whether someone looks healthy, but whether their overall cardiovascular risk is low.”
About Dr Pinakin V Parekh
Dr Pinakin V Parekh is a General & Interventional Cardiologist and Founder & Medical Director of Trident Heart Centre in Singapore. With more than 20 years of experience, he provides care across general, preventive and interventional cardiology.
His clinical interests include coronary artery disease and cardiovascular risk management, including high cholesterol, hypertension and diabetes. He also assesses symptoms such as chest pain, breathlessness and palpitations.
Dr Pinakin completed his cardiology residency at the National Heart Centre Singapore and subsequently undertook fellowship training in interventional cardiology at Liverpool Heart and Chest Hospital in the UK through the Health Manpower Development Plan scholarship. He also holds a Graduate Diploma in Family Medicine.
