Is a Vegan Diet Healthy?

Though it is certainly possible to eat a healthy vegan diet it is not inevitable.  Sometimes it’s “all in the name”….and this is indeed one of those times.  The terms “vegan” and “plant-based” are often used interchangeably.  The truth is that the two ways of eating can be very different.

Eating “vegan” means consuming nothing that originates from an animal.  Other than that, anything goes.  There is no requirement to choose healthier foods.  Although vegan diets encompass fruits, vegetables and other healthful whole foods, also on the table are more questionable items such as processed fake meats, soft drinks, French fries, onion rings, white bread and pasta, potato chips and donuts.  As you can see, it is actually quite easy to eat an unhealthy vegan diet.

“Plant-based” however implies more than simply avoiding animal products.  The term has an inherent connection with healthiness and the choosing of foods that will supply all the nutrients needed for excellent health while limiting those that can be detrimental.  Plant-based diets are usually made up of only foods originating from plants.  Nevertheless, dietary patterns can also be “plant-based” but allow some animal foods as well.

The transformation to a vegan or a plant-based diet is undertaken for many different reasons.  For some it is concern for animal welfare or the health of the environment.  In these instances, the criteria for food choices will likely concentrate on eating foods that are not derived from animals and are produced in an environmentally friendly manner.  On the other hand, if health improvement is an objective, it is necessary to know the kinds of foods that have the ability to accomplish this.  Luckily, nutritional research has already explored this very topic.


Some of the available evidence for the effect of food choices on health outcomes

 “Healthful and Unhealthful Plant-Based Diets and the Risk of Coronary Heart Disease in U.S. Adults” (1)

In 2017, researchers looked at information from over 200,000 men and women who had taken part in the Nurses’ Health Studies and the Health Professionals Follow-up Study regarding their risk for coronary heart disease.  This data included almost 5 million person-years of follow-up.

For the study, an overall plant-based diet index (PDI) was created, assigning positive scores to plant foods and reverse scores to animal foods.  From the PDI, a healthful PDI (hPDI) and an unhealthful PDI (uPDI) were established.  Distinguishing between healthy and less healthy plant foods was accomplished through known associations of the foods with chronic conditions (type 2 diabetes, cardiovascular disease and certain cancers) as well as obesity, hypertension, lipids and inflammation. The number of servings of each food per day was also taken into account.

For the hPDI scoring, positive scores were given for healthier plant foods (whole grains, fruits, vegetables, nuts, legumes, vegetable oils and tea/coffee) and reverse scores were given for both less healthy plant foods (fruit juices, sugar-sweetened beverages, refined grains, potatoes and sweets/desserts) and animal foods (animal fats, dairy, eggs, fish/seafood, meat (poultry and red meat) and miscellaneous animal-based foods).

For the uPDI scoring, positive scores were given for less healthy plant foods and reverse scores were given for animal foods and healthy plant foods.


Higher adherence to the overall PDI was associated with lower incidence of coronary heart disease.  This association was considerably stronger for the hDPI.

The uPDI was associated with higher incidence of coronary heart disease.


Even a slightly lower intake of animal foods combined with higher intake of healthy plant foods was associated with lower risk of heart disease.  However, focusing completely on healthier whole plant foods had the most positive outcome.  This is because eating animal foods and consuming less healthy plant foods are both associated with increased risk of coronary heart disease.

The researchers recognized the wide variation in the nutritional quality of plant foods and stressed that food quality is a crucial consideration in the healthfulness of a diet based on plant foods.

The long follow-up times included in this study demonstrated the long-term cumulative positive effects of a healthier form of a plant-based diet.


“Changes in Plant-Based Diet Quality and Total and Cause-Specific Mortality” (2)

A study from 2019 looked at the effects of improving the quality of a plant-based diet over a 12-year period.  This investigation used a similar PDI, hPDI and uPDI index system as was used in the 2017 study.


Improving the quality of a plant-based diet was associated with lower risks of both total mortality and cardiovascular mortality.

Increased consumption of an unhealthful plant-based diet was associated with a higher risk of total mortality and cardiovascular mortality.

There was a 10% drop in total mortality for those eating a healthy plant-based diet

There was a 12% increase in total mortality in those consuming an unhealthy plant-based diet.

Increasing healthy foods in the diet by 10 points reduced the risk of cardiovascular disease…

…by 7% in an overall plant-based diet

…by 9% in a healthier plant-based diet

Degrading the unhealthier plant-based diet by 10 points increased the risk of cardiovascular disease by 8%.


Increasing intake of healthy plant foods and decreasing intake of less healthy plant foods or animal foods lowers the future risk of mortality.


“Plant-based dietary patterns and incidence of type 2 diabetes in US men and women” (3)

In 2016 researchers examined the association of an overall plant-based diet and healthful and unhealthful versions of a plant-based diet with incidence of type-2 diabetes.  Using data from three prospective cohort studies (Nurses’ Health Study, Nurses’ Health Study 2 and Health Professionals Follow-up Study), the investigation included over 100,000 men and women followed for more than twenty years.  The degree of adherence to plant-based diets, both healthful and unhealthful, was examined for associations with the risk of diabetes.


A diet emphasizing plant foods and minimizing animal foods was associated with a reduction of about 20% in the risk of diabetes.

A diet consisting of principally healthier plant foods was associated with a larger 34% reduction in diabetes risk.

Conversely, a plant-based diet high in less healthy plant foods was associated with a 16% increased risk of diabetes.


Increasing intake of healthy plant foods while moderately reducing intake of animal foods (especially red and processed meats) is still beneficial for prevention of diabetes.  However, a diet high in less healthy plant foods increases diabetes risk.  Embracing the healthiest plant foods can cut the risk of diabetes in half.


Putting this information into practice

The science examined here and many more investigations have shown us that increasing the intake of healthy plant foods while reducing intake of unhealthy plant foods and animal foods can lead to health improvements.  But what is the best way to accomplish this goal?

There are a myriad of ways to increase plant foods in your diet but basically, they boil down to just two procedures – slowly reducing the intake of animal foods or immediately cutting out animal foods completely.  Both of these approaches can lead to improved health results but we have already seen that bigger changes mean better results.  Once again, we can look at scientific investigations that have examined the degree of success of each of these methods.

The “ease in” approach to dietary change, where there is a gradual reduction of animal foods along with a slow increase of plant foods, appears on the surface to be a more comfortable way to go.  However, it has been discovered that more significant dietary changes lead to faster appearance of sizeable health improvements.  Favourable changes in well-being can be extremely rewarding, increasing commitment to diet modifications and resistance to temptations to lapse into old habits.

Research on changing diets to improve diabetes management or reduce cardiac risk has shown that adopting a completely plant-based diet is remarkably well accepted by the patients themselves who can see and feel its benefits.  They experience subjective changes like increased energy levels, fewer aches and pains and less bloating but also discover other improvements that are measurable.  Shortly after a dietary change that includes substantial increases in healthy plant foods along with decreases in unhealthy plant foods and animal foods, indices such as blood sugar, cholesterol and blood pressure begin to improve and body weight starts to fall.  Perhaps most importantly, eating a healthy vegan or plant-based diet puts control of health into the hands of the consumer, a very satisfying place to be.  Conversely, small dietary improvements produce slighter, less noticeable health changes that may not offer enough encouragement to withstand the desire to slip back into previous eating patterns (4).


How to set yourself on the fastest trajectory to robust health

It is up to you to decide how to eat.  This article has pointed out benefits from simply decreasing unhealthy foods and increasing healthier ones but, in this discussion, we have looked at the research pointing to the greater advantages of going totally plant-based.  If you are looking for the fastest improvements in your health, here are the steps to get you there.

Eat mostly healthful foods by focusing on whole plant foods including fruits, vegetables, legumes, grains, nuts, seeds, herbs and spices.

Avoid unhealthful plant foods including products containing refined sugars (cakes, pastries, cookies, sugar-sweetened beverages), refined grains (white bread, white pasta, flaked cereals), processed foods, oils (plant-derived or otherwise), plants high in saturated fat (coconut, palm oil) and excess salt.

Avoid all animal-sourced foods (red meat, processed meat, poultry, fish, dairy products and eggs).

Make tap water your main beverage.  Tea and coffee are healthy additions too.


To help you along, try some of the delicious plant-based recipes to be found on the following websites;




 1  Sarija, A., Bhupathiraju, S.N., Spiegelman, D. et al.  Healthful and Unhealthful Plant-Based Diets and the Risk of Coronary Heart Disease in U.S. Adults. J Am Coll Card 2017; 70(4): 411-422.

 2  Baden, M.Y., Liu, G., Satija, A., Li, Y., Sun, Q., Fung, T.T., Rimm, E.B., Willett, W.C., Hu, F.B., Bhupathiraju, S.N.  Changes in Plant-Based Diet Quality and Total and Cause-Specific Mortality. Circulation. 2019 Sep 17; 140(12):979-991.

3  Satija, A., Bhupathiraju, S.N., Rimm, E.B., et al. Plant-based dietary patterns and incidence of type 2 diabetes in US men and women: results from three prospective cohort studies. PLoS Med. 2016;13(6):e1002039.

4  Trapp, C., Barnard, N., Katcher, H.  A plant-based diet for type 2 diabetes: scientific support and practical strategies.  Diabetes Educ. Jan-Feb 2010; 36(1):33-48.






Promoting a healthy adventurous lifestyle powered by plants and the strength of scientific evidence.

My name is Debra Harley (BScPhm) and I welcome you to my retirement project, this website. Over the course of a life many lessons are learned, altering deeply-rooted ideas and creating new passions.

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