A balanced, whole food plant-based diet is arguably one of the best diets for supporting healthy weight loss.
Whole food plant-based diets seek to entirely exclude all processed and animal-based food products from the plate to maximise the benefits experienced on a plant-based or vegan diet.
As a result of freshly grown produce as primary food sources, these diets tend to be incredibly low in fats and saturated fats.
In addition, they are cholesterol-free.
For this reason, alongside boastful amounts of fibre, high water content, and low-calorie density, whole food plant-based diets may be the best for weight loss.
According to Dr Michael Greger, M.D., “a whole-food, plant-based diet is the single most successful weight loss intervention without calorie restriction or exercise ever published in the peer-reviewed scientific literature and proven in a randomised controlled trial.”
The success comes as no surprise with the knowledge that these diets release glucose over much more extended periods due to the complex carbohydrates (carbs that take a long time to break down into sugars within the body).
Longer lasting energy should mean feeling hungry less frequently.
Suppose you are interested in weight loss without counting calories, temporarily starving yourself, or perhaps looking for a solution for weight loss goals to maintain energy levels. In that case, whole food plant-based could be your best bet.
Let’s start with fibre.
Fibre is found within plant-based foods and is a structural component within plants.
Our body cannot digest this by itself. We instead rely on bacteria to assist with the digestive task.
Our large bowel is host to many trillions of microbes.
Some are pathogenic (disease-causing), but most are highly beneficial for our internal well-being.
The gut microbiome (the world of microbes within our digestive system) plays a vital role in regulating immunity, inflammation, sleep and indeed has power over our ability to gain or lose weight.
Some migrating birds have demonstrated that weight loss/gain to prepare for a flight can occur without increasing food or fat consumption.
Could microbes influence the bird’s body to prepare for long flights?
There are various ways microbes can achieve changes to our weight loss or gain.
Hormones can make you feel full or nauseous and hold great power over your appetite and satiation.
A high fibre diet will take far fewer calories to fill the stomach.
A full stomach will cause PYY hormones to be released into the blood by the small intestine far sooner than a fat-dense diet. These hormones signal to your brain that you are full and causes the familiar uncomfortable sensation towards the end of a heavy meal.
Increasing fibre and packing the stomach with low-calorie plant structures instead of fats is enough in itself to cause weight loss.
Picture 100 calories of oil. A mere tablespoon.
Compare this with 100 calories of tomatoes, around four whole cups.
The low-calorie density is partly due to the high fibre content.
Fibre is low in calories. Some calories are locked away in the structures and can make you feel full while limiting the number of calories you can consume in one sitting.
Let us go back to the microbiome.
With control over our satiety hormones and fat storage, aiming for a flourishing community of microbes is a staple ingredient for any weight loss plan.
To allow this community to flourish, we need to feed it.
When we feed it, we can also extract more from our food.
Fibre is, in essence, a long chain of sugars.
Imagine something like this:
Each ‘s’ represents glucose/sugar.
When we consume table sugar, we consume something more like this:
s s s s s s s s s s s s s s s s s s s
Simple sugar, like the above, are already in their simplest form and can pass into the blood through the gut walls very easily.
When your meal reaches the small intestine, most simple sugars will be on their way into the bloodstream.
With simple sugars in the blood, they rapidly increase blood glucose.
In addition, by the time our meal reaches the large bowel, the glucose will be mainly in our bloodstream and not available for microbial consumption.
Compare this with the first structure in which the ‘s’ (glucose) molecules were in a chain form.
This chain would need to be broken at multiple points before a single glucose molecule would be free to enter the blood.
Bonds between glucose molecules make it take longer to break down into glucose.
The complexity or length of the chain is known as carbohydrate complexity.
Our bodies do not digest fibre.
Some calories remain trapped within indigestible cell walls.
As a result, they make it to the large bowel relatively untouched.
Fibre can help clean out the bowels and keep things moving, which could theoretically reduce inflammation should toxins be entrapped within your intestine.
Reduced inflammation could lead to weight loss and is achieved by most who opt for a whole-food, plant-based diet.
I stress the ‘could’ in the previous sentence as there may be a correlation between inflammation and obesity, but this is not to say that this will cause any other individual’s weight loss/gain.
These fibres (prebiotics) can be broken down and consumed by microbes in the gut microbiome.
They excrete the remains (metabolites), which our bodies can utilise!
While fibre serves no nutritional benefit in its undigested form, microbes break fibres down into compounds that we use in various ways.
Concerning weight loss, they could allow us to extract more energy from our food and keep us going that little bit longer – perhaps preventing an additional snack craving!
Fibre can make a tremendous difference to weight loss simply because it locks away calories that require a great deal of breaking down to extract.
It takes up plenty of space in the stomach and makes you feel full.
It can work wonders for the microbiome in the bowels, which regulates hormones and weight loss.
A beneficial approach would be to start small and gradually build up your fibre intake over several months.
Transitioning to a whole food plant-based diet for weight loss should help you achieve this.
Next, the water content of a whole food plant-based diet can lead to weight loss.
Like fibre, water is not a source of calories but takes up plenty of space within the stomach.
Picture the tomato, packed with juices!
The water content ultimately takes up a great deal of space.
Around 80-90% of the plants we eat are water.
That will fill our stomachs up much in the same way fibre does.
Full stomachs mean hormonal releases that should sooner or later result in the cessation of consumption.
Again, without filling you with calories.
So, in this case, you could theoretically eat more and still experience the weight loss associated with a whole food plant-based diet.
The main takeaway is that calorie density plays a vital role in managing weight loss or weight gain.
But this is not as plain and straightforward as calorie restriction resulting in one outcome, where calorie excess results in the other.
Calorie restricted diets are low in energy but likely also low in fat.
Whole food plant-based diets are low in fats.
Ultimately, if it is fat you wish to lose, then it is fat you want to avoid!
Energy/calorie restriction can only limit your energy levels.
While we can store away excess, it is not as simple as “obese people are simply eating too many calories”.
Typically, they’re eating simple carbs paired with fats.
Think here of the pan-fried pizza—oil, dough and nothing whole grain in sight.
Therefore, it may be advisable to focus on caloric intake and how much of our macronutrient intake comes from fats versus complex carbohydrates.
It, like most things, boils down to quality over quantity.
One last note, exercise is vital.
Exercise is vital for weight loss via calorie burning and further benefits the gut microbiome by increasing microbe diversity.
Adequate, consistent sleep and any lifestyle improvements will all help in addition.