The internet is full of heated debates about the “perfect” human diet.
While passionate advocates exist on both sides, let’s cut through the noise and look at what research actually tells us about whole food plant-based and animal-based diets.
Health Outcomes
Simply put, Plant-Based Wins:
The most compelling evidence for plant-based diets comes from large-scale population studies. The EPIC-Oxford study, which followed over 65,000 people for over a decade, found that vegans had lower rates of heart disease compared to meat-eaters. Plant-based eaters showed a 22% lower risk of heart disease, likely due to lower blood pressure and cholesterol levels.
No study is perfect, but these outcomes can be and are replicated time and time again in different populations around the world.
When it comes to cancer prevention, the World Health Organization’s research arm classified processed meat as a Group 1 carcinogen and red meat as a probable carcinogen.
Meanwhile, the American Institute for Cancer Research consistently finds that diets rich in whole plant foods help prevent various cancers.
A 2019 review in the Journal of the American Heart Association found that plant-based diets were associated with a 25% lower risk of developing type 2 diabetes. The high fiber content and complex carbohydrates in whole plant foods help regulate blood sugar levels more effectively.
However, in some instances animal-based wins:
Animal-based diets aren’t without their merits.
The most notable advantage is better absorption of certain nutrients.
A 2016 study in Critical Reviews in Food Science and Nutrition showed that heme iron from meat is absorbed 2-3 times more efficiently than plant iron. B12, found naturally only in animal products, is crucial for nerve function and DNA synthesis.
Weight Management
The research here is mixed, but interesting patterns emerge.
A 2015 meta-analysis published in the Journal of General Internal Medicine found that those following vegetarian diets lost an average of 4.4 pounds more than those on non-vegetarian diets.
However, this doesn’t tell the whole story.
Well-planned animal-based diets, particularly those emphasizing lean proteins, have shown excellent results for weight management too.
The high protein content helps with satiety and preserving muscle mass during weight loss.
A 2020 study in the American Journal of Clinical Nutrition found that lean meat consumption, when combined with resistance training, led to better body composition outcomes compared to plant protein alone.
Athletic Performance
Gone are the days when athletes believed they needed meat to perform. More elite athletes are proving that both approaches can work.
The key factor isn’t whether the protein comes from plants or animals, but rather getting adequate amounts of it.
A 2019 study in the International Journal of Sport Nutrition and Exercise Metabolism found no significant difference in strength or endurance gains between vegan and omnivorous athletes when protein intake was matched.
Environmental Impact
This is where plant-based diets shine brightest.
According to a comprehensive study published in Science in 2018:
- Producing 100g of protein from beef generates 50kg of greenhouse gases
- The same amount of protein from peas generates just 0.4kg
Water usage tells a similar story:
- 1kg of beef requires about 15,400 liters of water
- 1kg of lentils needs just 1,250 liters
Land use is perhaps the most dramatic: animal agriculture uses about 83% of farmland while providing only 18% of our calories.
Practical Considerations
Plant-Based Diet Challenges:
- Requires B12 supplementation
- May need to plan more carefully for iron, zinc, and omega-3s
- Initial learning curve for cooking and meal planning
- Can be harder to meet high protein needs without processed foods
Animal-Based Diet Challenges:
- Higher cost for quality sources
- Environmental impact
- Need to watch saturated fat intake
- Potential increased cancer risk with high red meat consumption
Making Your Choice
Both diets can be healthy when well-planned. Plant-based has the edge in terms of current science and environmental impact.
The key factors to consider are:
- Your personal health goals and any existing conditions
- Your ethical stance on animal products
- Your budget and access to quality foods
- Your cooking skills and time availability
- Your environmental priorities
The Bottom Line
Based on current evidence, a whole foods plant-based diet appears to have the edge for disease prevention and environmental sustainability. However, a well-planned animal-based diet using high-quality sources can also support excellent health outcomes.
Perhaps the most important thing isn’t choosing one extreme or the other, but rather:
- Eating mostly whole, unprocessed foods
- Including plenty of vegetables regardless of your choice
- Limiting processed foods and added sugars
- Choosing quality sources (whether plant or animal)
- Maintaining consistency with your chosen approach
Remember, the best diet is one you can stick to long-term while meeting your nutritional needs and aligning with your values. Don’t let perfect be the enemy of good – any step toward more whole foods is a step in the right direction.
