THE VEGAN DIET
Updated: Feb 23, 2021
So we're deciding to switch over to Veganism?
After years and years of building muscle on an omnivorous diet, we're now looking to make the switch to a more ethical and healthy lifestyle alternative?
If you are yet unfamiliar with it's growing popularity via social media, netflix documentaries or online marketing campaigns, you may be in for a real treat.
Much like Keto and Flexible Dieting, the Vegan diet has seen a sudden national rise in popularity in the last few years. While the exact numbers is hard to quantify, it is believed that around 2.5 million Australians currently consume a diet where almost all is vegetarian[26].
Veganism is becoming a polarizing subject in the nutritional world. There is a growing promotional trend of the vegan diet encompassing a healthier and more ethical alternative to most other non-vegan diets.
But.
Like many diets, individuals often jump onboard the latest and greatest dietary movement without making an informed decision first.
The Vegan Diet is not without it's own set of challenges and efforts required to appropriately adhere to.
Whilst this article weighs the pro's and con's of following a therapeutic vegan based diet, it is ways encouraged to self-determine whether or not you can succeed following any diet before jumping onboard.
So what are the costs of a Vegetarian or Vegan diet? Let's dive right in!
ON PROTEIN
If we're an everyday Joe or Jane with 0 interests in building muscle or changing body composition this may not interest you immediately...
However if we're an aspiring bodybuilder or physique athlete, how much protein we'll be consuming on a vegan diet can mean the difference between 'maintaining' current LBM (Lean Body Mass) or beginning the process of muscle loss.
Why?
Part of the untold truth is it is very difficult to getting the right macronutrtient ratio in to support MPS (Muscle Protein Synthesis) on the vegan diet. In order to meet our daily MPS requirements we must also be factoring in total daily Protein NET balance.
NET balance is largely composed of two opposing systems of:
Protein Synthesis - building up of amino proteins
Protein Degradation - breaking down of amino proteins
Similar to the Calorie Thermodynamic model, the more net Protein Synthesis we experience the more muscle we will build. Whilst the more Protein degradation we are in the more protein amino turnover occurs.[19]
Part of following the traditional vegan diet means you will be consuming lesser amounts of protein than usual.
How much exactly?
A traditional vegan protein intake of 50-60g would put you at roughly 30%-35% of your daily recommended protein intake requirements, just enough to maintain nitrogen balance[17,18].
In most cases, lean body mass (density) is unable to maintain on a vegan diet as there is an insufficient amount of protein amino acids required for MPS (NET balance) to occur typically resulting in loss of LBM[9,10]. Furthermore whilst adequate protein (30%-35%) is consumed for maintaining nitrogen balance, weight loss typically occurs as a result from loss of LBM.
Bodybuilders and Physique athletes require a greater amount of daily protein intake for maintenance of LBM and strength than sedentary individuals. Whilst endurance athletes require more-so an even greater amount of protein intake to counter the catabolic effects of cardiovascular exercise.
So if we're a bodybuilder or physique athlete coming from consuming 1g of protein per lb of bodyweight, you may find yourself consuming less than half your daily protein requirements for building muscle.
On the context of building muscle on a typical vegan diet:
Are we consuming enough protein to achieve maintenance of nitrogen balance? Yes absolutely.
Are we maximizing our muscle building potential? Most probably not!
On Leucine
Present accumulating ^evidence suggests meal distribution of daily protein is important[5,6]. Part of the muscle building mechanisms aside from muscle blood flow and amino acid transporters is the anabolic growth signaling from the amino acid leucine[7].
Leucine is known to stimulate the initiation of MPS provided adequate protein intake is consumed within an adequate time frame. Whilst there is evidence supporting equal protein meal distribution to optimize MPS, there is also evidence finding no difference between equal distribution of meals compared with 1-2 large meals[8].
Animal products in particular animal sources carry a plethora of important nutrients and amino acids required for fueling the body's demands for repair and growth. Whilst there is amino acids i.e. leucine available in plant based sources, the amount is significantly much lower than animal sources[4].
Whilst it may still be somewhat possible to maintain muscle and strength on a vegan diet, it can also come at a cost. If you are vegan you would typically need to ingest more protein overall to get an adequate amount protein amino acids.
ON SUPPLEMENTATION
For an average individual it is more difficult to get in a range of high quality protein sources from high protein vegan foods. Part of the problem is most food sources are often incomplete sources of protein aminos and often coupled with a higher Carbohydrate/Fat ratio.
Protein amino acids aside, animal products also contain important vitamins and minerals i.e. Vitamin A, B1, B2, B3, B6, B12, D, E, Biotin, Choline, Calcium, Chromium, Copper, Fluoride, Iodine, Iron, Pantothenic acid, Phosphorus, Potassium, Selenium, Sodium, Zinc.[1]
Whilst most vegetables are rich in vitamins, there are common deficiencies among vegans. Some of the most common include: Vitamin B-12, D, Calcium, Iron and Zinc[12,13,14,15].
A past review examined the nutrients found in fish alone (n-3 fatty acids, proteins, selenium, iodine, vitamin D, and taurine) and their possible associations with lowering CVD (Cardiovascular disease)[23].
Albeit most plants today contain vitamins and minerals from a variety of differing plant sources. Some of the required nutrients also exist in forms that are difficult for plants to digest/absorb. Omega fatty acid availability and absorption also requires special attention as absorption of EPA/DHA (algal) omega's aren't as potent as animal sources.[11]
A past study also looked at the differences between animal (wpi) protein & high quality (hydrolyzed) plant protein potency. Whilst the high quality vegan plant sources are still absorb able and 'safe', it appears to still be inferior to WPI's role via MPS absorption for the most part.
After equating both sources for leucine content, they found high quality plant proteins of no bio-equivalence when compared to WPI[38].
Whilst animal protein sources are an important source of complete proteins, vegetable proteins may also be required to meet some of the net protein requirements alongside the added micronutrient health benefits[20].
For the standard person on a vegan diet NOT looking for body composition improvements or optimal muscle building / retention this is ok. For those looking to improve or maintain their body composition this may be problematic as you may need to further consider over-ingesting calories to meet daily protein requirements.
A switch to protein/vitamin supplementation may also be needed for economical reasons and avoid any extra gastrointestinal discomfort (high fibre intake).
ORGANIC Vs CONVENTIONAL
The rise of the veganism movement in conjunction has seen a rise of bio-friendly available groceries and produce. The organic industry has also seen a massive growth spurt in recent years with recent numbers at $2.6 billion nationally & $97 billion US wide reportedly[27].
Organic food production and practices is most often promoted as sustainable and eco-friendly due to the lack of synthetic pesticides, genetic modifications & ionizing radiation.
Prices are also generally higher for organic produce than conventional. Largely due to production costs i.e. greater labor input as most farmers don't produce enough product volume to lower overall costs.
Organic food supply whilst growing is still comparatively limited than on demand.
However the question remains;
is Organic better than Conventional food?
A past review looking at the differences between organic and conventional food, health improvements, pesticide exposure found very few direct assessments on actual health outcomes.
Whilst there is a growing number of findings in observational research i.e. health benefits from organic food in certain dietary demographs, there is still yet a definitive stance on the health outcomes according to a recent systematic analysis[39].
Organic food is often hailed as healthier and more nutritious compared to conventional food. Conventional foods are generally higher in nitrogen whilst organic foods are generally higher in phosphorous[28].
Organic produce is generally slightly higher in Vitamin C, whilst lower in protein content but contains higher protein quality[29]. Most other nutrient findings tend to be statistically indifferent according to research.
On the context of nutrient content between both production methods, the large scientific body answer appears to find little to no difference with most research authors concluding insufficient evidence to suggest differences between organic and conventional foods impact on health, productivity and sustainability[30].
What about Raw Food?
The raw food craze has only recently appeared in the last 10 odd years. Being firstly promoted in the western world for 'civilized' humans following the laws of nature's lack of cooking utensils and cooking methods.
Despite the fact that a raw food diet is very difficult to follow, there is still a general belief of genuine health benefits by millions. Currently there is still very little science backing the raw food craze to help separate it from fact and fiction.
A past systematic investigation was performed looking at the prevalence of both contamination levels and risk of infection from the microbiological safety of raw foods. From various food categories, it was concluded certain L. monocytogenes & Flammulina velutipes from edible mushrooms should be avoided with a potential risk for harmful human disease[31].
A past study also looked at varying samples of raw food in conjunction with hygiene and storage practices. Based off their results, basic food safety standards is mostly overlooked with findings of pathogenic microorganisms in raw food items including raw meat & vegetables along with poor food surface contact posing further high risk[32].
In recent studies looking at the use of frozen raw food use in cases of allergic disorders, there were positive findings on the affect of antigenic potency of frozen materials being used[33].
Consumer knowledge whilst primarily focused on food hygiene and cleanliness may benefit from further education on the relationship between raw food treatment, handling, transport & storage along with the potential dangers from eating non-cooked raw ingredients.
With the discovery of numerous antibiotic-resistant isolates whilst still drawing a public health concern can be useful for improving Chinese regulatory authorities and framework to improve overall raw food safety.
On Denaturing
It is long believed one of the benefits of raw food consumption is the absence of the denaturing process. Recent literature has correlated the amount of ordered secondary structured content of proteins relative to their denatured state.
This also includes the degree of compactness ratio & native state of hydrodynamic volumes[34].
What does this mean?
Whilst a raw egg is less bio-available and digestible (50% absorbed) when compared to a cooked egg (90% absorbed). It's believed the denaturing process from cooking i.e. thermal heat, beating, blending, scrambling, air stress etc. can also impact how the protein molecules unfold[35].
Whilst the evaluation of the effect on structure in the denatured state has been difficult. Based off current evidence long-range interactions with respect to temperatures stabilize residual protein structure under denaturing conditions[36].
Overall, Denaturing does not necessarily mean the destruction of protein molecules.
VEGANISM BENEFITS
From what is currently known, there is an association of Veganism with lower levels of obesity CHD (Coronary Heart Disease) & CVD (Cardiovascular disease) [16,24].
Wholefood plant based Vegan (whilst somewhat nutrient lacking^) tend to be higher in nutrients, water and fibre. There is evidence of cancer risk being less prevalent in vegetarians than non-vegetarians.
There is opposing evidence of vegetarians experiencing lower risk of diabetes, liver fat[21] and eye cataracts. On the context of caloric restriction, there seems to be no additional beneficial impact of reduced red meat intake and increased fiber intake when calories are equated[22].
There is also evidence that a strict vegan diet confers health advantages as opposed to a standard non-vegetarian diet.
It is believed some part of the improvement in health is associated with the microbiota (gut) profile.
The relationship between diet appears and the intestinal microbial profile suggests vegans display a more distinct gut microbiota more-so than omnivores. Including reduced pathobionts, reduced inflammation and increased protective gut species[2].
There are also a growing movement of individuals choosing to follow vegan dietary practices for ethical and dietary reasoning. On the context of sustainability, one must also take into account dietary adherence for long term success.
Research suggests individuals whom endorse and follow the vegan diet for ethical reasons will adhere to the diet longer than those following for health reasons only[3].
Whilst there has been some extensive research into the health benefits of a vegetarian diet vs a non-vegetarian diet, Little is still known on the long term health benefits of vegetarian and vegan diets. One such recent study comparing red meat vs white meat vs non meat found little to no differences in blood / LDL cholesterol overall[37].
According to a large cohort population study (post confounding factor adjustments) there appears to be no significant difference in all-cause mortality between vegetarians, semi-vegetarians, pesco-vegetarians & non-vegetarians[25].
On the context of weight management however, the Vegan diet isn't magic. Iif you eat less or equate calories at the end of the day you will lose weight & improve your health!
SUMMARY
The Vegan diet is renowned as being ethically and morally superior to other non-vegan diets, however there is still much left unclear on the gains and / or losses that typically take place on a therapeutic vegan diet.
To surmize:
If you're looking for a more ethically sound diet and are not too heavily invested in building or maintaining muscle, Veganism may be for you.
If you're looking for a more health-based diet and are still heavily invested in building and / or maintaining muscle, Veganism may not be sustainable long term. Note: making a switch to a Pescatarian or Mediterranean diet may also suffice.
With proper planning, preparation & mitigation effort, Veganism may very well be your diet and one you can stick to long term!
References:
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