Intermittent fasting has gained immense popularity as a method for weight loss and overall health improvement. Among the many variations of intermittent fasting, the One Meal A Day (OMAD) diet is one of the most extreme approaches. As the name suggests, OMAD involves eating only one meal per day, typically within a one-hour window, while fasting for the remaining 23 hours.
The OMAD diet is more restrictive than other intermittent fasting methods, such as the 16/8 method, where individuals eat during an 8-hour window and fast for 16 hours. While some people claim that OMAD helps with weight loss, metabolism, and longevity, scientific research presents mixed results. Some studies highlight its benefits, while others warn of potential health risks.
Understanding the Omad Diet
The OMAD diet is based on the principle of prolonged fasting, allowing the body to enter a deeper state of ketosis, where it burns fat for fuel. Many proponents of OMAD believe that it simplifies meal planning, reduces calorie intake, and leads to weight loss. Additionally, some studies have suggested that fasting for extended periods can improve metabolic markers such as blood sugar levels, cholesterol, and inflammation.
A study by Varady et al. (2013) examined alternate-day fasting, which includes periods of eating one meal a day. The study found that participants who followed this fasting method experienced significant weight loss and improved cardiovascular health markers. These findings suggest that fasting can be an effective weight management tool.
However, while weight loss and metabolic improvements are possible with OMAD, research also indicates potential drawbacks. A study by Sun et al. (2023) revealed that consuming only one meal per day is associated with a higher risk of mortality in adults aged 40 and older. The research further suggests that skipping meals, particularly breakfast, increases the likelihood of developing cardiovascular disease and overall mortality risk. These findings highlight the importance of a balanced eating pattern rather than extreme fasting approaches.
Risks of Eating One Meal a Day
1. Nutrient Deficiencies
One of the biggest concerns with OMAD is the potential for nutrient deficiencies. Since individuals following this diet consume only one meal per day, they may struggle to meet their daily requirements for essential vitamins and minerals. Nutrients such as calcium, iron, and vitamin D are crucial for bone health, immune function, and energy levels. A diet lacking in these nutrients can lead to long-term health issues, including weakened bones, a compromised immune system, and chronic fatigue.
2. Increased Risk of Heart Disease
Skipping meals, especially breakfast, has been linked to an increased risk of cardiovascular disease. Research from Sun et al. (2023) indicates that adults who follow an OMAD diet may have a higher likelihood of developing heart-related complications over time. This increased risk may stem from irregular blood sugar levels, higher cortisol (stress hormone) production, and poor cholesterol profiles associated with prolonged fasting.
3. Negative Impact on Mental and Social Health
The OMAD diet can have psychological and social implications. Eating only one meal per day can lead to feelings of isolation since social interactions often revolve around shared meals. Many cultures and social settings emphasize eating with family and friends, which can become difficult when following a restrictive diet. Additionally, extreme fasting can contribute to an unhealthy relationship with food, increasing the risk of disordered eating patterns such as binge eating or orthorexia (obsession with healthy eating).
4. Unstable Energy Levels and Performance Issues
Many individuals following OMAD report experiencing energy fluctuations throughout the day. Since the body lacks a steady intake of food, it may struggle to maintain consistent energy levels. This can negatively impact concentration, productivity, and physical performance. Athletes, in particular, may find it challenging to maintain endurance and strength when eating only one meal per day, as their bodies require a steady supply of nutrients to support muscle recovery and performance.
Interestingly, a study by Wei et al., (2019) on the fasting-mimicking diet (FMD) found that FMD, which is low in calories, sugars, and protein but high in unsaturated fats, provides several health benefits without the risks associated with OMAD. The study revealed that participants who followed the FMD for three cycles experienced reduced body weight, lower blood pressure, and improved insulin-like growth factor 1 (IGF-1), which is linked to aging and chronic disease prevention.
The FMD involves consuming small amounts of food that mimic the effects of fasting while still providing essential nutrients. This method allows for the benefits of fasting without the extreme calorie restriction of OMAD, making it a safer and more sustainable approach to improving health and longevity.
A More Balanced Approach to Intermittent Fasting
If you are looking for a sustainable way to incorporate fasting into your lifestyle without the risks associated with OMAD, consider the 16/8 method. In this approach, individuals eat within an 8-hour window and fast for 16 hours. This method allows for multiple meals per day, ensuring a more balanced intake of nutrients while still reaping the benefits of intermittent fasting.
The 16/8 method provides:
Better Nutrient Absorption: By spreading meals throughout an 8-hour window, individuals can ensure they get a variety of essential nutrients.
Steady Energy Levels: Unlike OMAD, which can cause energy crashes, the 16/8 method allows for more stable blood sugar levels and consistent energy.
Greater Sustainability: The 16/8 fasting schedule is easier to maintain long-term compared to OMAD, which can be too restrictive for many people.
Final Thoughts
While the OMAD diet may seem appealing for its simplicity and potential weight loss benefits, it comes with significant risks. The potential for nutrient deficiencies, increased cardiovascular risk, negative psychological effects, and unstable energy levels make OMAD a less-than-ideal long-term dietary choice.
Instead, a balanced approach to intermittent fasting, such as the 16/8 method or the fasting-mimicking diet, can offer the benefits of fasting while ensuring adequate nutrient intake. Nutrition experts often caution against extreme dietary patterns and emphasize the importance of a well-rounded diet for long-term health and longevity.
Before making drastic changes to your eating habits, consult a healthcare professional or a nutritionist to determine the best dietary approach for your individual needs. Longevity and optimal health are best achieved through sustainable and balanced nutrition, not extreme fasting methods like OMAD.
References:
Sun, Y. et al. (2023) ‘Meal Skipping and Shorter Meal Intervals Are Associated with Increased Risk of All-Cause and Cardiovascular Disease Mortality among US Adults’, Journal of the Academy of Nutrition and Dietetics, 123(3), pp. 417-426.e3. Available at: https://doi.org/10.1016/J.JAND.2022.08.119.
Varady, K.A. et al. (2013) ‘Alternate day fasting for weight loss in normal weight and overweight subjects: a randomized controlled trial’, Nutrition journal, 12(1). Available at: https://doi.org/10.1186/1475-2891-12-146.
Wei, M. et al. (2017) ‘Fasting-mimicking diet and markers/risk factors for aging, diabetes, cancer, and cardiovascular disease’, Science translational medicine, 9(377). Available at: https://doi.org/10.1126/SCITRANSLMED.AAI8700.
Author: Zainab Cutlerywala (INFS Faculty)
