Plant based diets, also known as Vegan or Vegetarian diets, have become very popular over the years. A Vegetarian diet can include animal product, just no meat. So, you can still have dairy, eggs, honey. A Vegan diet is a very strict Vegetarian diet which is 100% plant based and contain no animal products at all.
There are many different types of vegetarian diets available. These include.
- Lacto-Vegetarian diets which exclude meat, fish, poultry and eggs, and foods that containing them, but allow dairy products
- Ovo-Vegetarian diets exclude meat, poultry, seafood, and dairy products, but allow eggs.
- Lacto- ovo Vegetarian diets exclude meat, fish, and poultry, but allow dairy products and eggs.
- Pescatarian diets exclude meat and poultry, dairy, and eggs, but allow fish.
- A semi-Vegetarian diet, also known as a flexitarian diet, is mainly a plant-based diet but includes meat, dairy, eggs, poultry and fish on occasion or in small quantities. (Mayo Clinic, 2020)
People decide to follow a Vegan or Vegetarian diet for various reasons such as cultural or religious values, health reasons, ethical concerns, concerns over antibiotics and hormones entering the food chain from livestock, environmental concerns (Lawrence and McNaughton, 2019). Maybe meat is too expensive or not accessible and the person is forced to eat a mostly plant-based diet or perhaps they simply don’t like the taste or texture of meat.
A Vegan diet has become especially popular among young people aged 16-24 (Brun, 2016). The main reasons for young people are environmental concerns and animal welfare concerns. Social media influencers and celebrity endorsement is another reason a Vegan diet has become popular among the younger generation.
Initially there was talk that a plant based diet would lead to nutrient deficiencies, and unfortunately many people don’t research either a Vegan or Vegetarian diet before starting and end up mostly eating processed vegan foods high in sugar, salt and saturated fat (yes, even Vegan foods can be unhealthy!). However, done properly a plant-based diet has many proven health benefits. So, let’s look at some of those benefits.
- A plant-based diet is naturally high in fibre, which is a major reason why there are so many health benefits associated with it. Fibre Helps with weight loss and weight maintenance as it keeps you full for longer, and high fibre foods release energy lowly and gradually into your bloodstream, so you don’t get a big energy spike. Fibre is also extremely important for gut health. Fibre health prevent constipation, diverticulitis, haemorrhoids, reduces your risk of developing colon cancer and improves overall gut health. For more information on fibre read my blog Facts about Fibre. And for more information on how to keep your gut healthy why not have a look at my Probiotics and Gut Health blog.
- A plant-based diet is full of Vitamin C. Vitamin C deficiency is one of the leading nutrient deficiencies worldwide, particularly in low-middle income places, but not uncommon in high income areas either (Rowe and Carr, 2020). There are several causes of vitamin C deficiency, but the main one is a diet lacking fruits and vegetables (Carr and Maggini, 2017). Vitamin C is an Antioxidant, a substance that defends our body from ‘free radical’. Free radicals attack important structures in the body leading to cell damage causing illness. Plants make their own antioxidants to protect their structures from free radicals, we make some but not enough to protect our bodies from the many free radicals attacking daily, and if free radicals breach our defences, they cause damage leading to a wide variety of diseases (Benzie, 2003). That’s where the importance of eating plant foods comes in. Back in the stone age our diets were mainly plant based so we got most of our antioxidants from plants (Benzie, 2003). Our bodies didn’t have to evolve much because plants done most of the work with regards to our antioxidant defence system, so we became dependant on them. You can read all about the importance of vitamin C is my blog The Importance of Vitamin C.
- Weight loss and weight maintenance from following a plant-based diet has been scientifically proven in numerous studies. People who follow a plant-based diet, whether it be Vegetarian or Vegan, usually have lower Body Mass Index (BMI) than those you don’t (Spencer et al., 2003; Alewaeters et al., 2005). Now, this is only if they follow a healthy plant-based diet that isn’t full of processed high sugar, high salt, and high fat Vegan foods. Numerous studies have shown that a Vegetarian diet does encourage weight loss, and a Vegan diet is slightly more effective for weight loss (Barnard et al., 2009; Moore et al., 2015). Honestly, I feel that the weight loss is probably down to the increase in fibre.
- Reduces inflammation. Inflammation occurs due to several diseases such as cardiovascular diseases, cancer, and chronic inflammatory diseases. The elderly, overweight or obese individuals, individuals who smoke or take drugs, and individuals who live in areas with high levels or pollution can also express markers of inflammation in their blood (Watzl, 2008). Diets high in fruit, vegetables and wholegrains have been shown to reduce levels of inflammation in the body.
- A plant-based diet has been shown to improve blood sugar control. One study took 74 type 2 Diabetics and split them into two groups. One group followed a Vegetarian diet for 24 weeks, the other group followed a standard Diabetic for 24 weeks. Both diets were calorie restricted by -500Kcals/day. After the 24 weeks 43 % of the Vegetarian group were able to reduce their Diabetes medication, while only 5% of the other group were. The Vegetarian group lost an average of 6.2kg, while the other group lost an average of 3.2kg. The Vegetarian group showed a 30% increase in insulin sensitivity, while the other group only showed a 20% increase. Finally, the Vegetarian group showed a significantly greater reduction in visceral and subcutaneous fat (Kahleova et al., 2011). The difference in both groups increased once exercise was added to the mix. Type 2 Diabetes is 50% less prevalent among Vegetarians (Snowdon and Phillips, 1985).
- Cardiovascular disease (CVD) is one of the worlds leading cause of death. Around 77% of total death worldwide are cause by chronic diseases, and 48% of that 77% is from CVD (Kahleova et al., 2018). Numerous clinical trials looking at the effects of Vegan and Vegetarian diets on health have shown that these diets can not only prevent CVD, they are the only dietary patterns that can reverse CVD. They have also proven effective to reduce the risk of death from CVD (Kahleova et al., 2018). It’s important to remember that this only applies when the person follows a healthy plant-based diet which includes all and enough of important nutrients.
- Unprocessed plant based foods have been shown to reduce the risk of developing a plethora of chronic diseases, including chronic Kidney Disease (CKD)(Rocha et al., 2019). Studies have shown a higher incidence of stage 3 CKD among those who eat a lot of red meat and processed meat, compared to those who don’t (Rocha et al., 2019). Vegetable proteins (yes, you can get protein from vegetables!), have been shown to have a protective effect which can significantly reduce the risk of developing stage 3 CKD (Chauveau et al., 2019; Haring et al., 2017). Healthy plant based diets full of fruit & vegetables, legumes, wholegrains, nuts & seeds, fish, that are low in red meat, processed meat, refined sugar and salt are linked to a lower mortality rate in people who already have CKD (Kelly et al., 2017). Also, when Vegetarians were compared to non-Vegetarians they had a 52% lower risk of death from renal failure (Orlich et al., 2013).
So that’s all the proven health benefits I could find. Quite a few, right? It was difficult to find any risks associated with a Vegetarian or Vegan diet. The main risks associated with a Vegan or Vegetarian diet are all nutritional deficiency based, but a well-planned Vegetarian or Vegan diet is very capable or meeting all current dietary recommendations. It’s when they aren’t well planned that deficiencies may occur.
- Protein deficiency – It’s 100% possible to get the recommended 0.8g/kg per day of protein solely from plant sources. However, as animal proteins are complete proteins (they contain all essential amino acids), and plant foods are incomplete proteins (they don’t contain all essential amino acids), sometimes a deficiency it certain essential amini acids could occur. For example, beans are a good source of an essential amino acid called lysine but are low in methionine. Bread is a good source of methionine but low in lysine. When eaten together (beans on toast) they compliment each other and make a complete protein. Pairing vegetables & wholegrains; seeds & wholegrains; seeds & nuts are all ways to ensure you’re getting enough of all the essential amino acids.
- Omega 3 fatty acid deficiency – A Vegan and Vegetarian diet that omits eggs, fish and algae will result in low levels of omega 3 fatty acids eicosapentaenoic (EPA) and docosahexaenoic (DHA).
- Vitamin D deficiency is common even among non-Vegetarians/Vegans. Vitamin D levels depend mainly on how much sun a person is exposed to as it appears in very little food sources unless fortified into the food in the case of cereals and spread butter. Food sources are mainly animal sources-oily fish, liver, egg yolks and red meat. It’s recommended that you consume at least 15µg/day, most people don’t consume anywhere near that amount.
- Vitamin B12 deficiency- B12 is essential to produce DNA, haemoglobin, myelin, some amino acids and to produce energy from amino acids and fatty acids. Some B12 can also be produced in the colon by gut bacteria (Rocha et al., 2019). Adults should consume 2.3µg of B12 per day, but this can be difficult for Vegans as they depend on vitamin B12 fortified cereals, plant, or algae as a food source (Pawlak et al., 2013). B12 deficiency symptoms include weakness, heart palpitations, weakness, pale skin, shortness of breath, a smooth tongue, numbness or tingling in the extremities, or cognitive impairment (Rocha et al., 2019).
- Iron deficiency is one of the most common nutritional deficiencies in the world (Rocha et al., 2019). It is especially prevalent among Vegans and Vegetarians because the type of iron found in plant foods (non-haem iron or ferric acid) is not as easily absorbed by the body as the type of iron found in animal foods (haem iron). Also, many plant foods contain substances that inhibit the absorption of iron even more. Vitamin C helps increase iron absorption (Rocha et al., 2019). Symptoms of iron deficiency includes gastrointestinal disturbances, impaired cognitive function, impaired immune function, fatigue, shortness of breath, and unregular body temperature (Rocha et al., 2019).
- Calcium deficiency – long-term inadequate calcium consumption and absorption, especially in a young person under the age of 30, can prevent a person from reaching peak bone mass. This in turn can lead to Osteopenia or Osteoporosis down the line. Dairy is a very good source of easily absorbed calcium. You can get calcium from certain green leafy vegetables like broccoli, kale, cabbage, bok choy, turnip & mustard greens, and these are also easily absorbed sources of calcium. But not all leafy green have calcium that is well absorbed, for example spinach and rhubarb contain calcium but it is not well absorbed by the body (Rocha et al., 2019).
- Zinc deficiency – Vegetarians and Vegans who drink alcohol and eat loads of wholegrains and beans can be at risk for zinc deficiency. Alcohol inhibits the absorption of zinc, and the phytates in wholegrains and beans can bind to zinc and cause it to be lost with other waste being excreted from the body (Rocha et al., 2019).
- A bit of a random one here, one study showed an increase in mortality among Vegans and Vegetarians linked to the consumption of high amounts of canned fruits (Rocha et al., 2019). The high amount of refined sugar in the syrup probably had a lot to do with it but imagine death by canned fruit!
In conclusion, I believe when done properly a plant based Vegan or Vegetarian diet can be very beneficial for your health. It’s important you don’t just cut out meat and animal products and leave it at that. You need to replace the nutrient you’re losing by cutting out these foods with plant-based alternatives. If you’re thinking about going Vegan (no meat or any animal foods) then maybe try going Vegetarian first. It’s never a good idea to go from eating meat every day to cutting it out completely. Even just having one or two ‘meat free days’ per week and cutting back on red meat and processed meat would make a big difference to your health. Why not try a Vegetarian dish next time you’re eating out (when the restaurants finally open again!).
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