Do Fad Diets Improve Cardiovascular Health?

Cardiovascular disease is a common, but preventable, chronic condition. The key to preventing this disease is to follow a healthy diet ( 1 ). But with so many diets being discussed online, you’re not alone in wondering about the cardiovascular benefits of following a fad diet.

In June 2020, research carried out by Dr. D’Souza in Georgia looked at whether fad diets could be beneficial in improving cardiovascular health. D’Souza is a Resident Doctor in Internal Medicine at Emory University School of Medicine, Atlanta ( 1 ).

What is Cardiovascular Disease?

Cardiovascular disease is an umbrella term used to describe a wide range of conditions affecting the heart and blood vessels. Often, the disease is caused by excess fat consumption and lack of exercise. Fatty deposits build up within the internal organs, including the heart, brain, kidneys, eyes, and blood vessels supplying other areas of the body. This can lead to a range of complications, including strokes, heart attacks, and blood clots. Cardiovascular disease is a common cause of ill health and even death, but it can be prevented if healthy lifestyle choices are made ( 2 ).

Many people search for a healthy diet plan to prevent or reverse cardiovascular disease. This may include consideration of a low calorie or fad diet.

What Is a Fad Diet?

Scientists and dieticians are often developing new weight loss strategies. Advertising campaigns for self-claimed innovative diets often target social media channels or TV. With so many diets available to choose from, you may wonder what constitutes a fad diet.

Definition of a Fad Diet

A fad diet is a “restrictive diet with very few foods or an unusual combination of foods for a short period of time” ( 3 ). Quick weight loss is often the attraction of a fad diet. 

How is a Fad Diet Different than a Low-Calorie Diet?

Fad diets are prescriptive about dietary intake, whereas a low-calorie diet might not specify which foods you should (or shouldn’t) eat. Instead, they involve restricting dietary intake to around 1,200 (or fewer) calories to prompt weight loss.

Fad Diet Examples

Popular fad diets include:

  • Intermittent Fasting: This fad diet can be fulfilled in many ways with the key premise that food intake is restricted at certain times, but not others. Some people fast for a whole day at a time, while others limit their food intake to certain times of the day. Some may eat less for five days of the week, then eat as they wish for the remaining two (also known as the 5:2 diet).
  • Ketogenic Diet: This is a low carb, high-fat diet. Following a keto diet is believed to prompt the body to enter a state known as ketosis. In ketosis, the body is more efficient at burning fats for energy. It also stimulates the liver to produce an effective form of energy for the brain. As more fat is burned, weight loss may occur, making it a popular choice ( 4 ). If this sounds familiar, keto does have some similarities with the Atkins diet, which rose to fame in the 1990s. Both are considered a fad diet ( 5 ).

Many other fad diets have been developed, including:

  • Paleo diet – a diet based on eating a wide selection of plants and meat.
  • South Beach diet – a high protein, low fat, and low carb diet.
  • Dukan diet – a high protein, four-phase diet.
  • Vegan or plant-based diet – a diet that excludes meat, dairy, and other animal products.

Fad Diets and Cardiovascular Health: The Study’s Findings

Fad Diets and Cardiovascular Health

Diets that were considered to be fad diets for the purposes of D’Souza’s study included intermittent fasting and the ketogenic diet. The researchers studied both fad diets to analyze any improvements in cardiovascular health and reported the following results.

1. Intermittent Fasting

Researchers were optimistic about the effect of intermittent fasting on an individual’s overall health. Animal studies have shown that this fad diet reduces blood pressure, lowers fat levels within the blood, and aids weight loss ( 1 ).

While these effects are all positive, the researchers did note that fasting in this way could lead to rebound over-eating after a fast, or unhealthy food choices at mealtimes. When this occurs, any positive cardiovascular effects of fasting are jeopardized. It was also recommended that diabetic patients should discuss intermittent fasting with their doctor before commencing the diet, to avoid the risk of hypoglycemic (low blood sugar) events ( 1 ).

2. Ketogenic Diet

The research team agreed that a ketogenic diet could lead to initial weight loss. However, the restrictive nature of the diet makes it difficult to sustain for long periods. The researchers also noted that it is common for dieters to mistakenly consume saturated rather than unsaturated fat. Saturated fat increases fat levels in the blood and raises the risk of heart disease. Following the keto diet longterm can cause stiffened arterial walls and even higher risk of death ( 1 ). It is, therefore, unlikely to improve cardiovascular health.

However, keto does show potential for diabetic patients. Lower sugar and insulin levels were noted in mice who ate a ketogenic diet, suggesting this fad diet could help those with diabetes ( 1 ).


Although weight loss can improve cardiovascular health, researchers found limited evidence that intermittent fasting or keto diets were beneficial ( 1 , 2 ). More trials are therefore required before fad diets are recommended. Until then, weight loss should be your focus.

Regular exercise and eating healthily are key to weight loss but can be challenging to maintain. Phentermine is the most widely prescribed weight loss medication in the USA. It suppresses appetite and boosts energy for effective weight loss alongside diet and exercise. To begin treatment, discuss a phentermine prescription with your doctor.


1. D’Souza MS, Dong TA, Ragazzo G, Dhindsa DS, Mehta A, Sandesara PB, Freeman AM, Taub P, Sperling LS. From Fad to Fact: Evaluating the Impact of Emerging Diets on the Prevention of Cardiovascular Disease. Am J Med. 2020 Oct;133(10):1126-1134. doi: 10.1016/j.amjmed.2020.05.017. Epub 2020 Jun 19. PMID: 32569590.

2. NHS (2018) Cardiovascular disease.

3. BDA (2020) Fad diets: Food Fact Sheet.

4. Healthline (2018) The Ketogenic Diet: A Detailed Beginner’s Guide to Keto.

5. Wikipedia (2020) Atkins diet.