Table of Contents

Trending Diets: How Sustainable Are They Really?

June 9, 2022

Keto and Paleo diets have become popular, but how healthy and environmentally friendly are they?

In recent years, a variety of new and potentially questionable diets have become popular. Often, these are spread through social media rather than being explicitly recommended by a medical professional. These new diets raise questions about their effect on the health of the individual as well as their overall sustainability. 

First, it is important to consider the standards of a “sustainable” diet, as this definition can be subjective. The UN defines a sustainable diet as one with “Low environmental impacts which contribute to food and nutrition security and to healthy life for present and future generations.” They also state that “Sustainable diets are protective and respectful of biodiversity and ecosystems, culturally acceptable, accessible, economically fair and affordable; nutritionally adequate, safe and healthy; while optimizing natural and human resources.” This definition spans more than simply the environmental impact, but also whether or not the requirements of a diet would be accessible to everyone. This can include the cost of the staple foods, the area in which an individual lives, and religious restrictions regarding food. The definition also takes into account whether the diet provides an individual with proper nutrition. Improper nutrition can be especially damaging to children or those with medical conditions that require specific nutrient levels to be fulfilled. While many of these new diets do consider the nutritional effects on an individual, they don’t consider whether the regimen might have a high environmental impact, especially foods that contain animal products. 

One diet that has become extremely popular over recent years is the ketogenic (keto) diet. This is a diet consisting of low fat and high carb foods, such as meat, fish, eggs, butter, and cheese. It recommends that adopters avoid grains, starches, fruits, and beans—all of which are staples in households around the world. The ultimate goal of the diet is to lose weight at a fast rate by sending your body into ketosis, which happens when your body doesn't have enough carbohydrates to burn for energy. Instead, it burns fat and makes ketones, which the body can use for fuel. Studies have shown that benefits can include reduced seizures in children with epilepsy, as well as aid to those with brian disorders, sleep disorders, and to individuals with type 2 diabetes.

Still, the most popular reason for pursuing a keto diet is weight loss, which can potentially have negative effects on individual health if done too rapidly. It can be difficult to follow, and it is well known that a diet heavy on red meat, dairy, and other high-fat foods is potentially unhealthy. For instance, one daily serving of unprocessed red meat can lead to a 13% increased risk of death from cardiovascular disease or cancer. Furthermore, one daily serving of processed red meat can cause a 20% increased risk of death from these same diseases. This is because red meat is extremely high in cholesterol, saturated fats, and sodium. The long-term effects of the keto diet are also unknown, and it is important to acknowledge that diets that might lead to rapid weight fluctuation are associated with a higher risk of strokes, heart attacks, and death. This is likely due to the fast gain and then loss of weight which is very stressful to the body, making one more vulnerable to these health problems.

Furthermore, widespread adoption of the keto diet has potentially harmful effects on the environment because the diet revolves around consumption of animal products. In fact, the meat industry accounts for almost 60% of greenhouse gases from food production annually. In addition, a diet that emphasizes meat consumption therefore supports animal cruelty in industrialized agriculture. The conditions in these factory farms that prepare the meat and other animal products are often horrific, and the treatment of the factory workers are known to be inhumane. Ultimately, while keto may be effective at promoting quick weight loss or improving certain other conditions (if guided by a healthcare professional), the diet can cause harm to the health of the individual and damage to our environment.

Another diet that has been rising in popularity is the paleo diet, named after the foods that humans might have eaten during the Paleolithic era, which extended from approximately 2.5 million to 10,000 years ago. The diet of ancient humans was thought to include wild animals, fish, fruits, vegetables, nuts, and seeds, and the current incarnation is based on the idea that the human body is genetically mismatched to the modern diet that emerged with farming practices. The diet also puts an emphasis on exercise and staying active, which helps to achieve the overall goal of weight loss. Potential benefits include lowered blood pressure, healthy blood glucose, and improved cholesterol balance. However, this diet can be very difficult for an average person to incorporate in their day to day since it takes time and resources to buy fresh, local products and then to prepare that food at home. In addition, it takes time and often money to follow a robust exercise plan. Many people do not have this luxury, especially because the diet requires one to abstain from eating foods like grains and legumes, which are an affordable and nutritious group of foods.

Unlike the keto diet, the paleo diet is much less heavy on animal products. In fact, individuals are guided to avoid eating dairy products, and the diet emphasizes local, sustainable, organic and non-GMO foods and grass-fed meat options. However, even with this local sourcing, environmental damage is still prevalent. In fact, a grass-fed cow will use 35 percent more water and 30 percent more land than a conventional, grain-fed cow. 

When researching a diet to follow, an individual should consider a variety of factors: human health, environmental health, accessibility, and one’s ethics. It is essential for each person to consider the requirements of each diet and consult a registered dietitian before embracing a trending diet. Ultimately, it is of greater value to the mind and body to make informed choices and adopt change that is sustainable over the long term, both individually and globally.

Liana Krasnoff is an FFAC High School Fellow.