The Health Benefits of a Vegan Diet
According to a BBC Future survey, the number of vegans in the UK quadrupled in just two years, between 2016 and 2018 - and is still rising. Though there is a risk that cutting out animal products could lead to deficiencies in certain nutrients - like iron and Vitamin B12 – overall, it is now widely acknowledged that adopting a vegan diet can have a systemic, positive effect on human health.
If you’re considering giving veganism a try this coming Veganuary, you may be wondering what effect this will have on your quality of life, disease risk, and overall health. We’ve put together this guide, to give you a rundown of the basics.
Types of vegan diet
Before we delve into the many possible health benefits of adopting a vegan diet, it’s important to draw a distinction between “whole food vegans”, “junk food vegans” and everything in between. Where health benefits are concerned, not all vegan diets are made equal.
Veganism is defined as a diet free from animal products. This could mean eating a perfectly balanced, wholefood, plant-based diet. It could also mean eating nothing but Oreos for breakfast, lunch and dinner (yes, they are vegan!). It goes without saying that one of these diets is inherently healthier than the other.
Simply eliminating animal products from your diet should not be thought of as a golden ticket to overall health. However – as we’ll cover in the next section – there are some health benefits to be had just by cutting out animal products, like meat, fish, dairy and eggs.
The dangers of eating animal products
Most people are aware that some animal products, especially when consumed in large quantities, can have a detrimental effect on human health. We know, for instance, that eating red meat more than once or twice a week probably isn’t wise.
Unfortunately, the dangers associated with regularly eating animal products are far more complex and far reaching than many of us realise. We’ll discuss some of the main risk factors here, in relation to the two biggest offenders – meat, and dairy.
Animal products like meat, cheese, butter and milk are the main dietary sources of saturated fat. Decades of research show us that regular or excessive consumption of these foods can heighten levels of bad cholesterol in the blood, increasing the risk of heart disease and stroke.
One study featuring 29,000 participants and published in the American Journal of Epidemiology found that those who ate the most meat also, always, had the highest risk of developing heart disease.
Not only would ditching red meat significantly lower your risk of getting heart disease in the future, some studies indicate that it could actually reverse existing heart disease. One such study by Dr. Caldwell Esselstyn, one of the world’s foremost nutritional experts, found that patients suffering with severe arterial restriction due to cholesterol build up were able to improve blood flow and “clean” arterial clogs by adopting a wholefood, plant-based diet.
One of the biggest dietary myths that has been propagated in the Western World is that people need to consume meat to get enough protein. Not only is this not true – all protein essentially comes from plants, animals are just the middlemen – but animal protein is now understood to be harmful to human health.
One reason behind this is that cramming your diet full of animal products leaves less room for essential micronutrients and fibre-rich foods – more on this later.
Besides this, several studies have exposed a significant link between animal protein consumption and cancer cell growth. Though this may sound extreme, the biomechanical effect behind this phenomenon is, sadly, well documented. Scientists discovered that ingesting proteins which contain a high proportion of essential amino acids (like animal proteins), causes the body to overproduce a hormone called insulin-like growth factor (IGF-1). This hormone stimulates cell division and growth, in both healthy and unhealthy cells.
Most human beings are routinely exposed to dozens of carcinogens every day, in things like cleaning products, pollution, and cigarette smoke, for instance. Whether these dangerous substances ultimately cause cancer is partially determined by the body’s willingness to upregulate or downregulate unhealthy cell growth. Therefore, a person who consumes animal protein is more likely to develop cancer due to excessive IGF-1 production than a person who does not, where all other variables are the same.
The human body is naturally slightly alkaline (pH 7.35 to 7.45) and must maintain this state to function properly. Acidosis is a dangerous condition which can occur when the body’s pH drops below 7.35. While there are dozens of pre-existing and lifestyle factors that can cause acidosis (genes, stress, smoking, lack of sleep), the food we eat plays a big part. Foods like fresh fruit and vegetables have an alkalising effect on the body, while foods like red meat, processed meat, eggs, fish and dairy, have an acidifying effect.
Acidosis leaves the body vulnerable to illness and disease, as practically every bodily system is forced to work in sub-optimal conditions. Over time, chronic acidosis can lead to extreme fatigue, kidney problems, autoimmunity, and a whole host of other health issues.
One condition most frequently associated with chronic acidosis is osteoporosis. When bodily fluids become too acidic, the body will seek to alkalise itself by drawing alkalising minerals like calcium and potassium from the bones, effectively weakening them.
Cow’s milk is one of the biggest culprits where acid formation is concerned. This means that contrary to what we were brought up to believe, drinking milk can actively weaken our bones. It’s easy to doubt this phenomenon, given that the dairy industry has put so much work into making us believe milk is good for our health. Fortunately, there is now plenty of reliable research out there which exposes the truth of the matter.
One 12-year study featured more than 77,000 women between 34 and 59 years old. The results showed that women who consumed the most calcium from dairy foods experienced broken bones more often than those who rarely drank milk. Dairy’s bone weakening effect can also be observed on a global scale, by comparing countries with high milk consumption to those with low milk consumption. Consistently, countries where dairy does not feature prominently in a typical diet have far lower rates of osteoporosis. Countries where milk consumption is high – like the UK and United States - have among the highest rates of osteoporosis in the world.
Poor microbiome diversity
The human gut contains between 300 and 500 different strains of bacteria; we call this bacterial ecosystem the “microbiome”. Gut bacteria determine how your body responds to food, and how well you can fight off illness and infection (as most immune cells are found in the gut). A healthy microbiome is diverse (lots of different strains of bacteria) and balanced (no one strain vastly outnumbers the others).
The food you eat determines which bacteria grow in your gut. Consuming too much meat, dairy and processed food can lead to an overgrowth of certain bacteria. Plus, most bacterial strains prefer high-fibre plant foods. Therefore, eating a diet too high in animal products and too low in whole plant foods can throw your gut bacteria balance out of whack. This could leave you more at risk of developing Inflammatory Bowel Diseases (IBD), and bowel cancer.
Animal products like meat and dairy pose a particular threat to microbiome diversity, as they often contain antibiotics which were used during the farming process. These antibiotics can lay waste to your own healthy gut bacteria, as much as they did with the bad bacteria in the animals they were used to treat.
Fewer animal products, reduced risk
Accurately quantifying the dangers of animal product consumption is a huge challenge which even the world’s leading nutritionists have struggled with, primarily because most individual animal foods have a multi-faceted adverse effect on human health. For example:
- Promotes acidosis
- Contains animal protein
- Contains saturated fat
- Contains antibiotics
- Promotes acidosis
- Contains animal protein
- Contains saturated fat
- Contains antibiotics
The same is true – though to a lesser degree in most cases – with poultry, fish, eggs and other animal food sources. When you consider the fact that many meat eaters consume one or two different animal products with each meal, every day, it’s easy to grasp how devastating the long-term health effects of animal consumption can be.
The health risks of veganism
Most people could enjoy vastly improved health in both the short and long term, simply by cutting out animal products. However, doing so does increase the risk of becoming deficient in certain nutrients commonly found in meat.
The five most common nutrient deficiencies in vegans are Vitamin B12, Zinc, Vitamin D, Omega-3 fatty acids and Iron. Becoming deficient in any one nutrient can have a myriad of adverse health effects, so it’s important to make sure you still get enough of these key vitamins and minerals when meat is off the menu.
The good news is that Vitamin B12 is the only nutrient which is ONLY found in animal products (except for some artificially fortified cereals and other processed foods). Zinc, Vitamin D, Omega-3 and Iron can all be obtained from plant sources. Here are some of the main plant sources:
- Zinc – Beans, legumes, wholegrains, bean sprouts
- Iron – Green leafy vegetables, wholegrains, lentils, dried fruits, beetroot
- Omega-3 – Chia seeds, flaxseeds, hempseeds, walnuts
- Vitamin D – Green leafy vegetables
Most nutritionists recommend that vegans supplement their diets with a high-quality Vitamin B12 supplement, as this cannot be obtained from plant foods. Whether you choose to supplement with any other vitamins or minerals is a matter of personal choice and should depend on the types of plant food you eat.
If your diet is heavily comprised of convenience vegan foods, meat substitutes, and other processed products, taking a well-rounded vegan multi-vitamin supplement is strongly advised.
The greater variety of whole, unprocessed, plant foods you consume, the better the nutrient profile of your diet. However - unless you plan and prepare your menu to prioritise diversity and avoid vegan junk food altogether (where’s the fun in that?) - it is extremely difficult to make sure you’re getting enough of everything. Though to be fair, the same is true of omnivorous diets!
What’s the healthiest vegan diet?
If your aim is to design the ultimate, health-promoting vegan diet, keep in mind that adding the good stuff in is every bit as important as taking the bad stuff out. So, what do we mean by the “good stuff”?
According to the NHS, the healthiest vegan diets are based primarily around whole plant foods and contain minimal processed or pre-packaged products. If it only has one ingredient on the label, or no label at all, you’re probably on to a winner. The bulk of this “ideal” diet should be wholegrains, fruits, vegetables, beans, legumes, nuts and seeds.
The more different foods like this you can cram into your diet, the better. The word “different” is key here, as it’s important to eat a wide variety of wholefoods to ensure your nutrient needs are met.
As for what to avoid, the following foods should make up a very small part of your diet or be omitted altogether:
- Refined oils
- Refined sugars
- Processed foods with added sugars or chemicals (like convenience foods, fizzy drinks, sweets and vegan chocolate)
- White or refined grain products (like white bread)
The benefits of a wholefood vegan diet
Adopting a diet comprised mainly or entirely of whole plant foods is – according to any nutritional scientist or dietician worth their salt – one of the most effective ways to maximise overall health.
Such diets are typically fibre-rich and packed full of health-promoting vitamins and minerals. Eating this way can dramatically reduce your chances of developing just about every chronic disease, while encouraging weight loss, and maximising total body vitality.
Adding these whole plant foods in, while cutting harmful animal products out, creates a petri dish for ideal health. To maximise this effect and give yourself the breathing space to eat a little junk food on occasion, we highly recommend taking a comprehensive vegan multivitamin supplement.
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