Written by Michael Dermansky
With growing concerns about both health and the impact on the environment, more people are concerned or are thinking about moving to a more plant-based diet, but is it better for your health? Why is plant-based food actually important for your diet?
Plant-based food is your body’s main source of carbohydrate, your brain’s preferred source of fuel and energy. Although carbohydrate has a direct effect on the release of insulin in the body, most carbohydrate derived from real, whole fruits and vegetables, are slow-release and causes a steady and prolonged release of carbohydrate and insulin in the body, unlike refined carbohydrates such as bread and sugars. Carbohydrate is essential to your body for the building of muscle mass, which makes you stronger and is also important for managing your weight (muscle mass has the most direct effect that you can control on your basal metabolic rate and your total energy expenditure). The reason is two-fold, carbohydrate is used together with protein to enter your cells to build muscle (protein doesn’t enter your cells alone, it does it through a gate that requires the 2 elements) and insulin, released with carbohydrate is required for the process of building muscle. In addition, carbohydrate is the preferred source of fuel for your brain. If carbohydrate is not present, your brain relies on ketones for energy which is not as good, can make you drowsy, and causes a slight acidity to your blood, which your body has to later correct by blowing off the acid from your lungs (which can give you bad breath).
Our main source of fibre is also derived from Plant-based food. There are two types of fibre, with very different roles. Soluble fibre, contained in fruits such as raspberries, kiwi fruit, and oats is important for managing our blood lipid (fat) content. Soluble fibre “grabs” onto cholesterol and pulls it out of your bloodstream, improving your blood lipids. Insoluble fibre, such as in celery improves your bowel health by being both the main source of fuel for your bowel and improving movement through your bowel, making you regular and reducing your risk of bowel cancer.
Finally, Plant-based food is our main source of other nutrients such as vitamin C, folate (important for healthy cell replication, especially during pregnancy) and B-carotene for healthy eyes, and potassium for normal heart function.
When Should I Eat?
The choice of high-energy (High Glycaemic Index/Load) or low-energy (Low Glycemic Index/Load) has the biggest effect on metabolism and both are important if selected at the right time.
Low Energy Carbohydrates, should be consumed at every meal, for the slow release of energy over time during the day. More specifically, the amount would be:
- 1-2 Cups per meal
- This includes food such as green leafy vegetables such as spinach and Bok choy, carrots, eggplant, Broccoli, and legumes
- If in doubt about selection, unprocessed and the more colours the better
High Energy Carbohydrates, should be consumed within the first 3 hours after “intense” exercise (heavy weights training or high-intensity interval training, not after a gentle stroll) for the purpose of replenishing your body’s natural short-term energy stores (glycogen) and to aid the process of building muscle. After exercise, the volume should be:
- 1 Cup of high energy carbohydrates together with 1 cup of low-energy carbohydrates
- This includes grains, pasta, and bananas
How To Ensure Protein Needs Are Met
The biggest challenge with a plant-based diet is meeting your protein needs for 2 main reasons, firstly no plant-based food has a complete profile of all the essential amino acids (building blocks of protein) that you require, so the combination of foods that you eat is very important and the protein content of plant food is much lower than meats, so you have to eat much more.
The problem is that grain-based food lack lysine (an essential amino acids, meaning that your body can not make it from other amino acids and it must be consumed), and legumes are low in methionine (another essential amino acid). In addition, all plant proteins are also low in leucine and tryptophan. Your body is constantly breaking down and re-making new proteins not only in muscle but in all the major processes in the body. All proteins require all the essential amino acids to be constructed, however, if an amino acid is not present in the process, it will not substitute it with another, it will just stop the process and then breakdown your muscle mass (your body’s natural reserve of protein) to get what it needs. This makes it very hard to build muscle mass to manage your weight.
So how do you do it? The answer is that it is very important to eat a combination of different types of plant-based food throughout your day. This means you have to eat legumes AND grain-based foods during the day (not necessarily at the same meal). It is easier to eat adequate protein if you maintain a lacto-ovo-vegetarian diet (eat dairy and eggs), rather than a strict vegan diet. In general, most vegetarians do meet their recommended daily intake of protein, but it is significantly lower than that of omnivores or those following a lacto-ovo-vegetarian diet, however, the micronutrient content of these foods is often not enough (most of the major B group vitamins, zinc, iron and calcium), therefore if you are to follow a plant-based diet, regularly see a dietitian or clinical nutritionist ensure you are meeting your nutritional needs.
Is A Plant-Based Diet Healthier?
In general, people following a plant-based diet have a lower weight and healthier cholesterol profile than meat eaters. This is due to a combination of lower energy intake (plant-based food are lower in energy density than meat-based foods) and plant proteins being lower in saturated fats, contain no cholesterol, are higher in fibre, and contain more anti-oxidants and phytochemicals, all helping to protect the body. Plant-based eaters also generally have lower blood pressure, reduced risk of type 2 diabetes, and reduced risk of ischemic heart disease, so lower risk of chronic diseases.
So if you are looking for a plant-based diet for your health and for the environment, there are some real tangible benefits for your heart, blood pressure, and waistline, but you need to plan what you eat to meet your full protein and nutrient needs. Please consultant a qualified dietitian or clinical nutritionist to hold your hand through the process to make sure you do this in a healthy way.
