Heart Attack and Weight

What is a Heart Attack?

A heart attack occurs when the supply of blood to the heart is blocked or limited, usually because of a blood clot or because of the narrowing of the coronary arteries (which are the arteries that supply the heart). This is life-threatening as it can lead to the death of parts of the heart. A heart attack may be caused by:

  • Obesity
  • High blood pressure
  • A high-fat and sugar diet
  • Smoking
  • High cholesterol levels.1

Symptoms of a Heart Attack

The symptoms of a heart attack can include the following:

  • Chest pain – this may radiate to the shoulder, arm, neck, or jaw
  • Sweating
  • Anxiety
  • Light-headedness
  • Wheezing
  • Nausea and vomiting.2

Chest pain is the most common symptom, but the symptoms are more likely to be subtler in people assigned female at birth (AFAB), with many of them dismissing the symptoms as the flu or acid reflux.3

Obesity Can Lead to High Blood Pressure

Obesity and hypertension (high blood pressure) are two contributing factors to heart attacks. High blood pressure may be caused by obesity, which means that the two can work together to increase the risk of suffering a heart attack.

Obesity is usually caused by eating foods with excess amounts of fat and sugar, alongside some other factors such as stress, portion sizes, medicines, and genetics.4

When a person is obese, they are likely to suffer from hormonal imbalances. One of these hormonal imbalances affects the system that controls blood pressure, known as the renin-angiotensin-aldosterone system.5

Renin is a substance that controls how much salt is in your blood to control blood pressure. In obese people, too much renin is released, which makes the body think the blood pressure is low. This results in angiotensin (a hormone that increases blood pressure) being released. Angiotensin works with aldosterone to increase blood pressure.6 

Furthermore, compression of the kidneys due to increased fat may contribute to obesity and hypertension. Normally, excess sodium (salt) is filtered out of the body and is concentrated in the urine. In obese individuals, compression of the kidneys means that the excess sodium stays in the blood.6 High sodium contributes to high blood pressure.

High Blood Pressure Can Cause a Heart Attack

Hypertension increases the risk of a person suffering a heart attack. This is because when blood pressure is high, the arteries get damaged.

The arteries are normally elastic, meaning that they can stretch to allow for blood to flow through. Constant blood flow prevents the blood from clotting. However, when blood pressure is high, the arteries become less elastic.7 This decreases the flow of blood through those arteries, which means that the risk of clots forming is increased. Furthermore, decreased blood flow can cause parts of the heart to die.

High-Fat Diets Increase the Risk of a Heart Attack

When a person eats fatty foods, the nutrients gained are fats. Fats are stored in the fat cells in the body, which helps to keep us warm, as well as acts as fuel storage. This fat may later be broken down to provide energy to the body at times when carbohydrates and sugars may not be adequate.

However, if a person eats excessive fats, this can lead to an increase in cholesterol in the blood. Cholesterol does have uses in the body; however, it is dangerous in high concentrations. When there is high cholesterol in the blood, it can enter the walls of the arteries and build up there, causing an atherosclerotic plaque.5 This plaque results in the artery becoming narrower, which is problematic for a few reasons.

Firstly, the plaque causes that part of the artery to become narrower (known as stenosis), which means that less blood can flow to that area. This may cause the cells in that area to die. This is significant since the coronary arteries, which supply the heart, may become atherosclerotic, which increases the risk of a heart attack.

Secondly, when cholesterol builds up in the artery walls, it can cause the inside of the artery to rupture. When this happens, substances that create blood clots go to the rupture site to try and repair it. This causes further narrowing of the artery, and the stenosis may become so severe that the artery is completely blocked. This causes the cells in that area to die. If this happens in the heart, this increases the risk of a heart attack.

Rapid Weight Loss Increases the Risk of a Heart Attack

Whilst it may seem like weight loss can reduce the risk of a heart attack, doing this too quickly may cause more problems. Rapid weight loss can affect the way that the heart beats- this is called an arrhythmia.8

Arrhythmias are usually harmless, however, in some cases, they can cause heart attacks very suddenly.9 Therefore, it is important to opt for progressive weight loss regimes, as this is more likely to provide safer and more consistent results.

When Should You Contact a Doctor?

If you are overweight or obese, it may be worth contacting a doctor to help you lose weight sustainably. Furthermore, a doctor can also carry out checks to see if you have any of the other heart attack risk factors, including high blood pressure and high cholesterol. Catching it early can help you to reverse these issues and reduce the risk of a heart attack.


Heart attacks are life-threatening and devastating. There are many contributing factors that can be resolved with lifestyle changes or medication and it is important to understand the risk factors so that changes can be made early. Spotting the symptoms can ensure a heart attack sufferer is attended to sooner, helping them to make a fuller recovery.


  1. Causes of heart attack [Internet]. nhs.uk. 2018 [cited 2022 Dec 5]. Available from: https://www.nhs.uk/conditions/heart-attack/causes/ 
  2. Symptoms of a heart attack [Internet]. nhs.uk. 2017 [cited 2022 Dec 5]. Available from: https://www.nhs.uk/conditions/heart-attack/symptoms/ 
  3. Heart attack symptoms in women [Internet]. www.heart.org. [cited 2022 Dec 5]. Available from: https://www.heart.org/en/health-topics/heart-attack/warning-signs-of-a-heart-attack/heart-attack-symptoms-in-women 
  4. Obesity [Internet]. [cited 2022 Dec 5]. Available from: https://www.bhf.org.uk/informationsupport/risk-factors/obesity 
  5. Jiang SZ, Lu W, Zong XF, Ruan HY, Liu Y. Obesity and hypertension. Exp Ther Med. 2016 Oct;12(4):2395–9.
  6. Hall JE, do Carmo JM, da Silva AA, Wang Z, Hall ME. Obesity-induced hypertension: interaction of neurohumoral and renal mechanisms. Circ Res [Internet]. 2015 Mar 13 [cited 2022 Dec 6];116(6):991–1006. Available from: https://www.ahajournals.org/doi/10.1161/CIRCRESAHA.116.305697 
  7. CDC. High blood pressure symptoms, causes, and problems | cdc. Gov [Internet]. Centers for Disease Control and Prevention. 2021 [cited 2022 Dec 6]. Available from: https://www.cdc.gov/bloodpressure/about.htm 
  8. Vedel-Larsen E, Iepsen EW, Lundgren J, Graff C, Struijk JJ, Hansen T, et al. Major rapid weight loss induces changes in cardiac repolarization. J Electrocardiol. 2016;49(3):467–72.
  9. Arrhythmia [Internet]. nhs.uk. 2018 [cited 2022 Dec 6]. Available from: https://www.nhs.uk/conditions/arrhythmia/ 

Aisha Hayat

Bachelor of Science - BS, Biomedical Sciences, General, University of Bristol

Aisha is a Biomedical Sciences graduate with an understanding about research techniques, the pharmacology of drugs and the pathophysiology of illnesses. She is currently working as a healthcare assistant and has experience of research being used in a clinical setting, as well as the process of diagnosing and treating illnesses.

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