There is no doubt that eating a plant-based diet does wonders for the body. Physical benefits include reducing the risk of chronic diseases and promoting sustainable weight management.
However, there is more to the plant-based diet than just the physical side of things.
Studies have found that vegetarians and vegans have happier mood states and more positive emotions compared to omnivores. That is, eating a plant-based diet is not only beneficial for our physical body but also contributes to our mental health and overall wellbeing too.
Mental health is understandably a complex topic. Many factors contribute to a person’s state of mind. One of these factors is something that we’re all familiar with: inflammation.
Everyone has a love-hate relationship with inflammation. We love it because it’s part of our immune system and we need it to survive. When we accidentally cut ourselves on a sharp edge, the open skin has the potential to invite bacteria and infection into the body. Thankfully, an inflammatory response usually prevents this from happening. But not so thankfully, the area is now red, sore, hot and swollen and takes a few days to go away.
A compound involved in the inflammatory response is known as arachidonic acid (AA). Through a series of reactions, the body converts AA into several inflammatory chemicals. In our early years of medical school, we learnt about AA through anti-inflammatory medications like aspirin and ibuprofen. These drugs block the conversion of AA and stops the inflammation cascade from occurring to relieve pain and swelling.
While we do need arachidonic acid, like with many other things, too much of it can cause harmful effects especially on our mental health.
Research has suggested that high amounts of AA in the body can promote inflammation in the brain. Arachidonic acid is often viewed in comparison with a compound known as docosahexaenoic acid (DHA). DHA is an omega-3 fatty acid and it has favourable effects on the brain.
When we put these two together, a high AA to DHA ratio has been associated with depressive symptoms.
Animal products, including chicken, eggs, beef, pork and fish, are incredibly high in AA. On the other hand, plant foods have negligible amounts. The current Western diet delivers a ratio of 15:1 in AA to DHA; signifying a very high intake of AA. Interestingly, years ago, when humans were hunter-gatherers, the intake of these compounds were at an equal ratio of 1:1.
A plant-based diet is notably low in both AA and DHA. This may provide an insight into the difference between the emotional states of omnivores and those on a plant-based diet.
What About Fish?
For those who are on top of their omega-3 game, you might be wondering about the effects of eating fish.
Fish products are high in omega-3 DHA. Therefore, a high DHA intake can potentially reverse the ratio and result in low AA to DHA.
A study has found that omnivorous diets rich in fish was associated with a lower risk of depressive symptoms compared to omnivores who didn’t eat a lot of fish. In reality though, many omnivores find it difficult to consume a diet ‘rich in fish’ which was defined as an average of 170g of fish per day in the study.
It is also worth noting that fish has a relatively high amount of AA too, making up 5.8% of the total intake of AA in America.
Putting it to the Test
Many studies associating a plant-based diet with improved emotions and moods were cross-sectional analyses. This means that while they were able to find a link connecting the two factors at that moment in time, they couldn’t say for sure which one came first. Perhaps those who ate a vegetarian diet were already happier beforehand.
So a first-of-its-kind randomised controlled trial in 2012 assigned omnivores to three groups:
- Control: ate meat, fish and poultry daily
- Fish: ate fish 3-4x weekly, no meat and poultry
- Vegetarian: no meat, fish and poultry
At the end of the 2 weeks, researchers found that the vegetarian group had improved their mood states and mental stress compared to the other two groups. The fact that these changes occurred within such a short time frame of 2 weeks is also quite astounding.
Similar studies trialled the plant-based diet in a workplace setting.
Employees of an insurance firm who were overweight and/or had a diagnosis of type 2 diabetes were split into 2 groups: low-fat vegan diet and control group. There were no other interventions in place such as portion-size control, calorie counting and exercise. After five and a half months, the vegan group reported improvements in general health, better sleep, more energy and increased vitality. Their mental health improved and not surprisingly, work productivity also improved.
The GEICO study took it one step further and studied employees from 10 major corporate companies. The results showed that a low-fan vegan diet given for 18 weeks in a corporate setting improved depression, anxiety and productivity. The employees also improved in body weight, cholesterol and blood sugar control.
At Embody Nourish, we believe that a nourished body is incomplete without a nourished mind. Mental health is understandably a complex topic. However, we think that everyone should be aware of how their diet can impact on their mental wellbeing. This way, everyone has the ability to make more mindful and positive choices in their every day lives if they wish.
From our research and personal experience, we certainly believe that eating a plant-based diet is associated with incredible physical and mental benefits. There is more research to be done about this topic but the results are promising and we’re excited to see what new data is released in the future.
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