A vegan diet is where one avoids all animal products and not just meat. Although it is a highly restrictive diet given the fact that majority of today's food come from animals sources, the vegan diet is still hailed as a healthy alternative. Its benefits include reduction of risk for heart disease, diabetes, and some cancers.

However, not all people are convinced that an all-vegan diet is the best choice nutritionally speaking. In his recent Yahoo News article, writer Chris Riotta warns that there are hidden dangers to a vegan diet that most people are unaware.

It may not be as healthy as one thinks according to Chris Riotta's Yahoo News article. Simply defined, being vegetarian means someone decides to forgo animal protein but does not necessarily mean that the person's diet is healthy and balanced according to nutritionist Shannon Kadlovski  in a Huffington Post Canada article.

To prove his point, Kadlovski points out the high estrogen content of processed soy including tofu, a common ingredient in vegetarian cuisine. Too much estrogen intake can cause hormonal imbalances. Pasta, another common vegetarian item, is heavily processed and lacks fibers which could create those unwanted blood sugar spikes common to all high glycemic index foods.

To boost his case, Riotta cited a 2014 study which compared four types of diets based on their nutritional quality: Vegan, Vegetarian, Semi-Vegetarian, Pesco-Vegetarian and Omnivorous Diet. The study went on to conclude that the vegan diet is the most restricted diet which results to it being the lowest in total energy intake and lowest protein due to the total elimination of animal products. In addition, the study observed that calcium intake was lowest in the vegan diet and is below national dietary recommendations.

It seems that Riotta is not the only one to suspect that a totally vegetarian is not only difficult but can be unhealthy. For example, Winston Craig PhD in his article for Vegetarian Nutrition warns of these possible nutrient deficiencies for people who wish to go on an all-vegan diet:

Vitamin B12 - This vitamin is abundant in meat, milk and eggs but can't be found in plants. Vitamin B12 deficiency could result in dementia, forgetfulness, memory loss, disorientation and nerve dysfunction.

Long chain omega 3 fatty acids - Omega 3 is essential for cardiovascular health, eye and brain function. However, this can only be easily obtained from fish which is not an option for full-fledge vegetarians. An alternative would be alpha-linolenic acid which is present in flaxseed, walnut, canola oil and tofu. Dr  Craig warns that although the body could convert the alpha-linolenic acid found in these plants, the conversion process in a fairly inefficient one which could mean the converted amount might not meet the body's requirement for optimal health and functioning.

Both writers concede that a healthy all-vegan diet is possible but it would require a lot of effort to pull it off. Due to the restrictive nature of an all vegan diet, people who want to pursue it might have a hard time finding ways to adequately answer the full range of the body's nutritional requirement. Sure, there are supplements available to augment certain nutrients that might be naturally lacking in a purely vegetarian diet, but it would mean that one has to be a nutritional expert or at least well-read enough to adequately assess which nutrients are lacking. To the common folks who lack the proper knowledge, an all-vegan diet may not be the best option.