In a Net Zero scenario, the global population cannot afford to be on the diet that they are on today. The reason being that there is not enough space to raise animals to feed 10 billion people on a meat-rich diet in 2050. Research from ‘Our World in Data’ shows almost half of the world’s habitable land used for agriculture and majority of this is used to graze animals. This causes harm to biodiversity and adds to climate change as forests are cut down to graze an increasing amount of animal. Currently, nearly than half of deforestation of tropical rainforests occurs to raise more cattle for beef and this is unsustainable in the long run with a growing world population. Only a plant-based diet is sustainable in a Net Zero world and a sustainable amount of meat a person can eat per week is 255g. This is the same as two chicken breasts.

Plant-based diets are a necessity of reaching Net Zero, but there are many personal benefits to adopting one and it can transform your health. One of the main health benefits of a plant-based diet is losing weight and keeping weight off. Many studies have shown that on the whole, plant-based diets reduce weight faster compared to low fat omnivore diets. A 2020 systematic review of the impact of plant-based diets on weight loss by Tran and colleagues showed consistently that those who followed the diet have a lower Body Mass Index (BMI). It worked for all types of groups of people, across gender, race and different stages of life. But is it guaranteed to work for you?

It can depend on which type of plant-based diet you adopt

There is a wide variety of diets that call under the category of plant-based diets such as Mediterranean, vegetarian, vegan, pescatarian and flexitarian diets. One study by Barnard et al (2021) compared the Mediterranean diets with vegan diets by putting two different groups on each diet. After 16 weeks, those on the Mediterranean diet lost 1.5 kg whilst those on the vegan diet lost 7.9kg in the same period. A review of clinical studies in 2016 that have compared weight loss in vegetarian and vegan diets showed there was more weight loss compared to non-vegetarian diets by 2kg on average. However, vegan diets performed better than vegetarian diets, as the average loss on a vegan diet was 2.5kg compared to 1.5kg with a vegetarian diet.

Other factors that impact the success of the diet

There are other factors that affect the success of a plant-based diet. How much weight you lose depends on how you eat and when you eat. Diets only work if they reduce the amount of sugar and saturated fat that you are eating. There are plenty of vegetarian and vegan food that are full of sugar and fats so be careful how much of this you consume! To benefit properly from such a diet, it should consist of mainly unprocessed food with a high intake of fruit and vegetables. When you eat matters too because eating the same food at different times of the day has an impact on weight loss. Eating a big breakfast and small dinner will reduce weight faster than having a small breakfast and a big dinner.