This article is the second in a series that aims to debunk widely held medical myths that have influenced beliefs and behaviours surrounding health and wellbeing.

Weight loss can be achieved with exercise alone

Exercise is undoubtedly an essential component of weight management and overall wellbeing however, relying solely on exercise for weight loss may yield limited results. Caloric intake plays a significant role in weight management, and exercise alone may not create the necessary net calorie deficit needed for a substantial weight reduction.

To illustrate this: a 30-minute moderate-intensity workout may burn approximately 200 to 300 calories, which can be easily offset by consuming a small candy bar, a muffin or a latte.

Added to the above are two additional “confounding” facts:

1, Compensatory behaviours

Engaging in exercise can sometimes lead individuals to compensate by increasing their food intake or adopting a sedentary lifestyle for the remainder of the day. Studies have shown that people tend to overestimate the calories burnt during exercise and underestimate the calories consumed, leading to a neutral or positive energy balance.

2, Metabolic adaptations

Excessive exercise can trigger metabolic adaptations in the body. This includes a decrease in resting metabolic rate, which is the number of calories burnt at rest and with a low level effort, again attenuating the magnitude of weight reduction efforts.

Having said that, exercise is obviously critical for wellness as it provides numerous health benefits beyond weight management, including improved cardiovascular health, mental wellbeing, and muscle strength.

A vegetarian diet is always healthy

There is a common misconception that adopting a vegetarian diet automatically guarantees good health. While a well-balanced vegetarian diet can provide numerous health benefits, including lower risks of obesity, heart disease and certain cancers, it is not inherently healthier than a diet that includes animal products.

For example, some vegetarian foods with high starch or high sugar contents can be very detrimental to one’s health. In addition, an unbalanced vegetarian diet could lead to deficiencies in protein, iron, zinc, calcium, vitamin B12, and omega-3 fatty acids, which are all essential for achieving and maintain a good health.

Plant-based iron sources (non-heme iron) are less readily absorbed compared to iron from animal sources (heme iron); however, pairing them with vitamin C-rich foods can enhance absorption.

A slim body equals a healthy body

The notion that a slim body is synonymous with good health oversimplifies the complexities of human physiology. Body weight alone does not reflect overall health status or the presence or absence of underlying medical conditions.

While obesity is associated with increased risks of various diseases such as diabetes, heart disease and certain cancers, individuals with a normal body mass index can still be unhealthy due to factors such as a poor diet quality, a sedentary lifestyle and metabolic abnormalities.

BMI has its limitations as it does not differentiate between fat mass and muscle mass, and fat-muscle distribution. Hence it is essential to focus on objective markers of good health, including blood pressure, lipid and sugar levels, and inflammatory and metabolic indices, rather than solely on body weight or BMI.

One can be slim from poor nutrition or calorie restriction but have diffuse vascular disease from relying mainly on high-fat, high-sugar diet or on processed foods. Also, many slender patients can be heavy smokers or alcohol drinkers, and the latter two conditions are effectively responsible for their body build wasting.

I am doomed because I have a family history of cardiac disease

While a family history of cardiac disease may increase an individual's risk of heart events, it does not necessarily condemn them to the same fate. Genetic predisposition plays a role, but lifestyle factors such as diet, physical activity and smoking, along with blood pressure, blood sugar and cholesterol management are equally, if not more, influential. By adopting a heart-healthy lifestyle, individuals with a family history of cardiac disease can significantly mitigate their risks and improve their overall cardiovascular health and longevity.

Here is some supporting data:

A large study published in The New England Journal of Medicine in 2016 examined the impact of a healthy lifestyle on the risk of coronary artery disease. It found that individuals with a high genetic risk, as indicated by a positive family history, had a significantly lower risk of developing CAD if they adopted a healthy lifestyle.

Another similar study published in the Journal of the American College of Cardiology in 2018 demonstrated that adherence to a healthy lifestyle was associated with a substantially lower CAD risk, irrespective of genetic predisposition.

Expired medications should never be used

On a slightly different topic than the above “myths”, this one is about the expiration date of medications, as the stated drugs expiry date does not necessarily indicate an abrupt loss of their efficacy or development of harmful compounds. Rather, it reflects the manufacturer's guarantee of optimal potency and safety until that date.

Many medications, if stored appropriately, remain stable and effective beyond their expiration dates.

However, certain medications, such as antibiotics, may lose potency or degrade over time. It is essential to consult healthcare professionals and exercise caution when considering the use of expired meds, but that option may be quite a viable one for some expensive drugs.

• Joe Yammine, MD is a consultant cardiologist at the Bermuda Hospitals Board. The information here is not intended as medical advice nor as a substitute for professional medical opinion. Always seek the advice of your physician