What is the criticism of raw veganism?

November 6, 2025 •

4 min read

According to a study published in the 'Journal of Nutrition', long-term raw vegan diets are often associated with low bone mineral density and an increased risk of specific nutrient deficiencies, which fuels the central question: what is the criticism of raw veganism? Concerns about health risks and nutritional inadequacy are at the core of the debate.

Quick Summary

The raw vegan diet is criticized primarily for its potential to cause nutritional deficiencies, specifically B12, vitamin D, and calcium. Health concerns also revolve around poor bone density, dental erosion, and potential for disordered eating. Experts suggest these risks arise from the exclusion of cooked foods and certain supplements, which can compromise overall health.

Key Points

Nutrient Deficiencies: Strict raw veganism puts individuals at high risk for critical deficiencies, particularly vitamin B12, but also vitamin D, calcium, and iron.
Bone Health Concerns: Reduced bone mineral density is a recognized risk, often linked to insufficient vitamin D and calcium intake.
Digestive Distress: The high fiber content can lead to gastrointestinal issues like bloating and gas, especially for those not accustomed to the diet.
Dental Erosion: The frequent consumption of high-acidity fruits and vegetables can lead to irreversible damage to tooth enamel.
Orthorexia Risk: The restrictive and obsessive nature of the diet can contribute to disordered eating patterns like orthorexia nervosa.
Limited Social Engagement: The dietary restrictions often make social situations involving food difficult, potentially leading to isolation.

Understanding the Raw Vegan Diet

Raw veganism is a dietary practice that involves consuming only uncooked, unprocessed plant-based foods. This includes fruits, vegetables, nuts, seeds, sprouted grains, and legumes. Proponents of the diet believe that heating food above a certain temperature (usually 104–118°F or 40–48°C) destroys valuable enzymes and nutrients. While some adherents report increased energy and weight loss, the diet faces significant and well-documented criticism from the scientific and nutritional communities concerning its long-term health implications.

Key Nutritional Deficiencies and Health Concerns

Vitamin B12

One of the most serious and widespread criticisms of raw veganism is the inherent lack of vitamin B12. This vital nutrient, crucial for nerve function and red blood cell formation, is almost exclusively found in animal products. As B12 is not synthesized by plants, raw vegans are at a high risk of developing a severe deficiency without supplementation. Symptoms of B12 deficiency can include fatigue, anemia, nerve damage, and cognitive decline.

Vitamin D and Calcium

Bone health is another major area of concern. Raw vegans have been shown in some studies to have lower bone mineral density compared to omnivores. This is likely due to the combined effect of a lack of vitamin D, which is often fortified in non-raw foods and primarily obtained from sun exposure, and potentially inadequate calcium intake. While plant-based calcium sources exist, their bioavailability can be lower than dairy sources, and the exclusion of fortified plant milks can exacerbate the issue.

Iodine and Iron

Iodine is critical for thyroid function, and deficiencies can lead to goiter and metabolic issues. While it is present in some sea vegetables, consistent and adequate intake can be challenging on a strict raw vegan diet. Similarly, iron from plant sources (non-heme iron) is less easily absorbed than iron from animal products (heme iron). The high fiber content of the diet can also inhibit iron absorption, increasing the risk of anemia.

Omega-3 Fatty Acids

While raw vegans can obtain alpha-linolenic acid (ALA) from flaxseeds and walnuts, the conversion of ALA to the crucial eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) is inefficient. EPA and DHA are vital for brain health and reducing inflammation, and without supplementation or a consistent intake of specific algae, deficiencies are a significant risk.

Digestive and Dental Issues

Excessive Fiber: The extremely high fiber content of a raw vegan diet can cause gastrointestinal distress, including bloating, gas, and diarrhea, particularly for individuals not accustomed to such high levels. While fiber is generally beneficial, excessive amounts can interfere with the absorption of certain minerals.
Dental Erosion: The high consumption of acidic fruits and vegetables, without the buffer of cooked starches or animal proteins, can lead to accelerated dental erosion. Over time, this can wear down tooth enamel and increase sensitivity.

Social and Psychological Criticisms

Orthorexia and Disordered Eating

One of the more serious criticisms of raw veganism is its potential link to orthorexia nervosa, a condition characterized by an unhealthy obsession with healthy or 'pure' eating. The strict rules and limitations of the raw vegan diet can create an environment where a person's life becomes dominated by food choices, potentially leading to social isolation and significant psychological distress.

Lack of Social Flexibility

The stringent nature of the diet often makes dining out and socializing challenging. Sharing meals is a fundamental aspect of many social structures, and adhering to a raw vegan diet can lead to feelings of isolation and make it difficult to participate in social events involving food.

Comparison: Raw Vegan vs. Cooked Vegan Diets


Feature	Raw Vegan Diet	Cooked Vegan Diet
B12 Intake	Requires supplementation	Often fortified in cereals and milks; supplementation also recommended
Nutrient Bioavailability	Lower for some nutrients (e.g., iron, protein) due to raw state	Higher for certain nutrients (e.g., lycopene, iron) due to cooking
Preparation Time	Often more intensive (sprouting, dehydrating)	Varies, but generally less restrictive and time-consuming
Vitamin D Source	Sun exposure, supplementation	Often from fortified foods and supplementation
Digestion	Can cause bloating from high fiber	Generally smoother; cooking breaks down tough plant fibers
Calorie Density	Typically lower, making adequate intake challenging for some	Higher calorie density options available from cooked starches, legumes

The Benefits of Cooking

Cooking food, a practice central to human evolution, offers several significant advantages that raw veganism rejects. Cooking breaks down tough plant fibers, making nutrients more bioavailable for digestion and absorption. It also destroys harmful bacteria and antinutrients that can be present in raw foods. For example, cooking legumes deactivates lectins and phytic acid, which can interfere with nutrient absorption. The argument that cooking destroys all enzymes and nutrients is an oversimplification; while some are lost, the benefits of enhanced bioavailability often outweigh the losses.

Conclusion

While the raw vegan diet may offer some short-term benefits, the significant criticisms regarding nutritional deficiencies, bone health risks, potential for disordered eating, and social inflexibility are crucial considerations. The lack of vitamin B12 is a non-negotiable issue requiring supplementation, and concerns over minerals like calcium, vitamin D, and iron should not be ignored. A well-planned, cooked vegan diet, which includes fortified foods and strategic supplementation, is generally regarded as a safer and more sustainable alternative for long-term health. Anyone considering a raw vegan diet should consult with a registered dietitian or healthcare professional to ensure proper nutrient intake and monitor their health. For more information on dietary guidelines, consult reputable health organizations like the National Institutes of Health https://www.nih.gov/.

Frequently Asked Questions

For most people, a long-term raw vegan diet is not recommended due to the significant risk of serious nutritional deficiencies, including a life-threatening lack of vitamin B12. It can be particularly dangerous without proper supplementation and medical supervision.

Since vitamin B12 is not found in plants, raw vegans must rely on supplements to meet their needs. There is no naturally occurring, reliable source of B12 within a strictly raw vegan diet.

Yes, many people experience weight loss on a raw vegan diet, primarily because it is often lower in calorie density than typical diets. However, maintaining a healthy weight can be a challenge due to the high volume of food required to meet energy needs.

The most common deficiencies include vitamin B12, vitamin D, calcium, iodine, and omega-3 fatty acids. Iron and protein intake can also be inadequate without careful planning.

No, cooking can actually increase the bioavailability of some nutrients by breaking down tough plant cell walls and inactivating certain antinutrients. While some heat-sensitive nutrients are lost, the overall nutritional benefit of cooking is often positive.

While a diet rich in fruits and vegetables can be protective, there is no conclusive evidence that a strictly raw vegan diet is superior in disease prevention. Many of the purported benefits are also available from a well-balanced cooked vegan diet without the associated risks.

Orthorexia is an unhealthy obsession with 'pure' or healthy eating. The strict and sometimes dogmatic nature of raw veganism, with its rigid rules about food preparation, can exacerbate or trigger this psychological condition in susceptible individuals.