I was recently interviewed by Global News for my opinion on the study results and on the Paleo Diet as an overall health and weight loss plan. You can read my quotes in the story “Will the Paleo Diet make you fat? Why this controversial study is angering diehard supporters“.
(Photo credit: zsoolt via Flickr).
Does the Study Show that Paleo Diets Make You Fat?
The fact that the researchers are going around drawing these types of a conclusions from a mouse study is ridiculous. Mice aren’t people, and it doesn’t take a scientist to know that. Any time a nutrition study is done in animals and not in people, don’t change your diet based on its results.
Another problem with this study and the claims of its authors: the mouse diet wasn’t really Paleo. The so-called “Paleo Diet” the mice were fed has 13% of its calories coming from protein, 6% from carbohydrate and 81% from fat. The carbohydrate was in the form of simple sugars.
In people, studies on Paleo Diets have had 35% of calories coming from carbohydrate in the form of slow carbs like vegetables, sweet potatoes, fruit. The Paleo Diet is not low carb!
The mouse comparison diet had 20% of its calories coming from protein, 70% from carbohydrate and 10% from fat. Interestingly, the carbohydrate in this diet was 50% starch and 2% simple sugars, meaning the rest was fibre. This is clearly healthier than the extremely high fat diet the mice were getting, without any fibre whatsoever.
Saying this mouse study proves the Paleo Diet causes weight gain and diabetes in people is just bad science.
So should you be trading your whole grains for grass-fed beef and coconut oil?
Here’s my take:
What is the Paleo Diet?
Also known as the caveman diet, this way of eating is based on what supporters think people ate during the Paleolithic era – before the development of agriculture about 10,000 years ago. The thought is if our hunter-gatherer ancestors didn’t eat legumes such as beans and lentils, grains, potatoes, dairy, refined sugar, salt and processed food then we shouldn’t either. The paleo diet consists of grass-fed meat (for a healthier balance of omega-3: omega-6 fatty acids), fish, eggs, vegetables and fruit, nuts and seeds.
Why Do Paleo Supporters Love the Diet So Much?
Paleo Diet advocates say it’s great for weight loss and lowering the risk of chronic diseases like heart disease and cancer. The problem – and it’s a major one – there isn’t evidence for these claims. Most of the studies we have on this diet are small and short-term.
But Does the Paleo Diet Help People Lose Weight?
Let’s start with some of the great things about the Paleo Diet: having guidelines on what to eat and what to avoid can help people have a specific reason to avoid processed foods, sugary drinks and other high calorie foods. Focusing on whole foods and avoiding processed foods is a good move from a health and weight loss perspective.
I’ve seen this diet work over the short-term for people who weren’t eating enough protein and vegetables because it forces you to do that. It can help reverse some of the high carb ways of eating people have gotten used to: cereal for breakfast, pasta and rice and potatoes at dinner. But all-or-nothing eating never works. Avoiding entire food groups isn’t a strategy people can stick to for too long.
The Paleo Diet definitely has a cult following. I have several clients who were Crossfitters and through that learned about the Paleo Diet. They noticed their energy levels were low and they weren’t losing weight. I worked with these clients to add some slow carbs to give them more energy for their workouts and all of a sudden they started losing fat.
(Photo credit: Kai Hendry via Flickr).
What Does the Research Say?
There is some evidence the Paleo Diet could be useful for weight loss. The most interesting Paleo Diet study to date was a Swedish study of 70 overweight, post-menopausal women. The women were assigned to either a Paleo Diet or a Nordic diet (high in fibre and low in fat) and followed it for 2 years, with the support of dietitians.
The Paleo group lost an average of about 10 pounds and 1.5 inches around their waists by the end of the study, while the Nordic group lost an average of 6 pounds and 0.8 inches.
While it seems the Paleo diet won the weight loss comparison, it was only compared to 1 type of diet. There are many other eating patterns that are healthier that haven’t gone head-to-head with Paleo in a randomized control trial.
We know that low fat diets aren’t satisfying. Choosing heart-healthy fats like in the Mediterranean diet is not only satisfying, but is hear-healthy. We have long-term studies suggesting this helps people lose weight and keep it off compared to other popular diets.
As my colleague Jennifer Sygo recently pointed out, so far all studies on the Paleo Diet haven’t controlled the amount of food people eat on various diets, and the Paleo group ends up eating fewer calories. Losing weight improves risk factors for heart disease and diabetes so this could explain some of the positive benefits seen in certain studies.
What are the Pitfalls of the Paleo Diet?
The Paleo Diet points the finger at the wrong enemy. Don’t blame legumes and whole grains for the rise in obesity and chronic diseases. Blame processed foods and our sedentary lifestyles!
We know legumes are incredibly healthy and great for the environment. The World Health Organization has declared 2016 as the year of the pulse and for good reason. It’s one of the healthiest foods on the planet.
Whole grains are also healthy foods rich in fibre, B vitamins and antioxidants. You just have to keep your portion sizes in check. About the size of a fist at a meal is a good amount for most people.
Eating large amounts of red meat isn’t healthy as it increases the risk of heart disease and some types of cancer. Decades of research suggest eating a mostly plant-based diet is the healthiest for preventing and managing chronic diseases.
The Paleo Diet also lacks variety, meaning people can get bored easily and go back to eating the way they were before and gaining even more weight.
Interestingly, there isn’t evidence our ancestors really ate this way. There’s even evidence to suggest they ate some grains and legumes. Cavemen and cavewomen also didn’t spend most of their days in front of a computer screen. They had to hunt and gather their food, staying active all day long. Also, the average life expectancy was 30… so it doesn’t make sense to eat like the Flintstones when we live like the Jetsons!
(Photo credit: Alfer22 via Flickr).
The Bottom Line
Any all or nothing diet sets people up for failure. Eat everything but choose healthier foods 80% of the time and less healthy foods 20% of the time. That’s something you can stick with over the long-term.
Before you start slathering coconut oil all over everything, remember: your ancestors didn’t have coconut oil and were super active! Choose a way of eating that includes healthy foods that are shown to promote health, like vegetables, fruit, legumes, whole grains, yogurt, nuts and seeds.