Is the whole30 diet the best for weight loss?

We’re back with another edition of debunking popular weight loss diets. My last version covered the paleo diet, and you can find it here.

I always want to give a balanced approach when talking about popular diets. So I’m going to talk about the pros and cons of the whole30 diet.

What is the whole30 diet? 

I'll say, to be fair to Whole30, they don’t market themselves as a weight loss diet. They're an elimination diet. 

The aim is to remove certain foods from your diet and then slowly reintroduce them to see if you notice anything. They say that after eliminating foods people can find that they have better sleep, more energy, an improved mood, and less cravings.

As the name suggests, you eliminate the foods for 30 days. You then reintroduce food groups individually over a 10 day period and monitor how you feel. You can then decide what foods to permanently reintroduce, after seeing how they affect you.

So, what foods make the cut in Whole 30? 

Foods to include: meat, seafood, eggs, fruit and veg, healthy fats, and herbs/spices. The goal is to eat ‘real’, whole, unprocessed foods.

Foods to avoid: grains, sugar and sweeteners, alcohol (even if used in cooking), legumes (think beans, lentils, soy), dairy, processed foods, carrageenan (a thickener), and sulphites (a preservative). 

Other rules: no weighing yourself – as the programme is more focused on how you feel, and not the way your body physically changes. Also, no recreating junk food with whole30 approved ingredients – the diet aims to change eating habits but if you’re continuing to eat the same foods then you’re not making a change, they say.

Now you’ve got a rundown of what the Whole30 diet is about, it’s time to start seeing if it has any promise.

Negatives of whole30: 

Straight away I could see a few issues with the diet.

It could lead to nutrient deficiencies: 

Any diet that is highly restrictive can run the risk of nutrient deficiencies. Whole30 cuts out entire food groups so there’s some key nutrients that may be harder to obtain. Here’s a few of the nutrients you’ll likely be missing out on.

Calcium – whole30 cuts out all dairy products, and dairy is a great source of calcium. And while calcium can be consumed from plant foods like green leafy vegetables and dried fruit, these are harder for our body to utilise. This is because plant sources of calcium also have a chemical called oxalate within the plant which limits the absorption. Not to mention that a lot of other plant based sources of calcium are on the whole30 avoid list like beans, pulses, and grains.

Fibre – the diet cuts out all grains and all legumes which are 2 food groups that are high in fibre. While you can get fibre from fruit and veg too, it could be difficult to get your recommended 30g of fibre a day just from these foods. Especially as you would have to eat a large volume of fruit and veg to get enough.

Plant based protein – if you’re a meat eater, then protein isn’t a concern as meat and seafood are all approved in the diet. But if you’re vegetarian or vegan, you may struggle. A lot of plant protein comes from grains and legumes and soy, but these are all on the avoid list. There is a plant based version of whole30 to follow that allows legumes, but not highly processed soy, or grains. It looks like you’ll need a lot of careful planning to ensure you get enough protein when following this diet.

As you can see, there's a lot to consider when taking on the diet, it's not as simple as they make it seem.

Also, getting support from a registered nutritionist or a dietitian is so important when doing an elimination diet to ensure you don’t have deficiencies.

It could be hard to stick to: 

Anything that is highly restrictive means it will be hard to stick to. While the whole30 website offers lots of encouraging words, meal plans, and recipes, it doesn’t change the fact that it will be a big change for a lot of people. And this makes it harder to follow. There isn’t a lot of foods in the list of what you can eat so this can make it difficult to make suitable meals. It will take a lot to be able to stick to the diet.

Thinking about it a bit differently, whenever I see a diet that tells you to cut out lots of foods, warning bells flash in my head. Any time you restrict yourself, it could lead to binge eating. As when you’re not allowed something, it makes you feel out of control and want it more. If you normally eat the foods on their avoid list, then suddenly quitting them for 30 days sounds like a recipe for disaster.

And not allowing yourself all of these foods at once can make you become preoccupied with food. It can slip into dangerous disordered eating territory. Their website even has a disclaimer that if you have a history of eating disorders, you shouldn’t take part in the diet unless you’re supported by a health care professional. This elimination diet is not something to take lightly.

The cost:

Another thing to consider when making changes to your diet is the cost. Whole30 focuses on meats, fish, fruit, and veg. And unfortunately, these foods can be more expensive when compared to ultra processed or convenience foods. It could be a challenge to buy enough of all the ingredients you need to make satisfying meals.

As you can see, there is a lot to consider when starting the whole30 diet. But let’s look at some positives too.

Positives of whole 30: 

Whole30 focuses on whole ‘real’ foods and encourages you to be more in tune with your body, so I have to give credit where it’s due. 

You’ll make healthier food choices: 

During your 30 days you’ll cut out all highly processed foods and sugars. And we know that a diet high in ultra processed foods can lead to negative health effects like heart disease and diabetes. It also means you’ll be eating lots of fruit and vegetables which are nutrient packed foods. So, all the foods you’ll be eating will be nourishing and support your health. This is an obvious advantage of the diet.

Allows for reflection on eating habits: 

Whole30 encourages you to reintroduce food groups one at a time and monitor how your body reacts to them. I think this sort of reflection is great as it allows you to be more in tune with your body. A lot of our eating habits are unconscious - we do them without thought. Being able to think about your food choices and question why you’re eating what you’re eating allows you to be more aware of what you consume.

They also say that people on the diet tend to have more energy, better sleep, increased focus, and have better digestion. And if you’re able to find an eating style that makes you feel energised and have a better mood, then that’s a win in my book!

Will whole30 lead to weight loss? 

The part you’ve all been waiting for. Will you lose weight when doing whole30?

The answer is yes. The whole30 diet cuts out a lot of foods, and particularly junk foods that are higher in calories. So by not eating these foods and instead having food like vegetables and meat, a person will lose weight.

The foods in the allow list (apart from fats) have a low calorie density, meaning you’ll have to eat large quantities to get the same number of calories. For example, 100g of allowed chicken breast has 106 calories, while 100g of not allowed chicken nuggets has 250 calories. So, by doing some quick maths, it’s clear that the whole30 diet is likely to be be lower in calories than what people may typically eat.

While whole30 don’t sell themselves as a weight loss diet, a lot of people will start it with the intention of losing weight and they’ll likely succeed.

The real question is whether the weight loss will last in the long term. If you’re able to stick to the diet, then you should be able to maintain the weight loss. But when you start reintroducing foods, you may be eating more calories and so weight gain is likely to occur. Long lasting weight loss really depends on what foods you reintroduce and how your eating habits will change long term.

When writing this blog post, I struggled to find any published research on the diet, so it doesn’t seem there is much evidence available on the longevity of the weight loss.

 

Overall, the whole30 diet has some good ideas, but it also has some issues. I think an elimination diet this extreme shouldn’t be undertaken unless you have a registered nutritionist or dietitian supporting you. This will make sure you're not missing out on any key nutrients and you’ll be able to get support when reintroducing foods.

Key points: 

• Whole30 is a 30 day elimination diet where you exclude grains, legumes, alcohol, sugar, sweeteners, dairy, and some additives. You then reintroduce food groups one at a time and see how your body feels.
• Some downsides of the whole30 diet is that it’s highly restrictive, could lead to nutrient deficiencies, is likely to be more expensive, and can be hard to stick to.
• Positives of the diet is that you’ll be avoiding highly processed foods and added sugars, which can be damaging to health when eaten in excess. It also allows you to eat mindfully and make note of how your body responds to foods.
• The diet is likely to lead to weight loss purely based on how restrictive it is. When all you can eat is meat, fruits, and vegetables, it will be easy to be in a calorie deficit. The real question is whether the weight loss will be maintained, and there isn’t a concrete answer available.

I hope you enjoyed this post! I’d love to hear your thoughts in the comments below.

Bye for now! 👋

References:

https://whole30.com/weight-loss-hub/

https://whole30.com/

https://whole30.com/plant-based/program-rules/

https://whole30.com/the-pancake-rule/

Healthy food is more expensive: https://pubmed.ncbi.nlm.nih.gov/26307238/

Restriction and binge eating: https://pubmed.ncbi.nlm.nih.gov/31443880/

Processed food and heart disease: https://pubmed.ncbi.nlm.nih.gov/31142457/

30g of fibre: https://www.nhs.uk/live-well/eat-well/digestive-health/how-to-get-more-fibre-into-your-diet/