Metabolic syndrome is widespread, affecting 34 percent of all U.S. adults and half of those over 60. (1) Instead of a distinct disease, metabolic syndrome is a cluster of symptoms. One is diagnosed if at least three of the following five markers are present: (2)
- large waist circumference
- high blood pressure
- elevated fasting glucose
- elevated triglycerides
- low HDL (“good”) cholesterol
Metabolic syndrome is a red flag, warning you that your body isn’t healthy. In fact, each of the symptoms listed above is a separate risk factor for diabetes and/or cardiovascular disease, two leading causes of death in the United States. (3, 4, 5) Fortunately, adopting a Paleo diet can reverse the markers of diabesity and metabolic syndrome and even help those who have already developed insulin resistance, as I will discuss in this article.
Metabolic Syndrome, Insulin Resistance, and Heart Disease – What Do They All Have in Common?
Metabolic syndrome, insulin resistance, and heart disease are all considered “modern” diseases because they weren’t prevalent until the 1900s after the Industrial Revolution. Drastic changes in U.S. dietary habits have occurred only in the last century or so, including increased consumption of hydrogenated oils (trans fats), vegetable oils, processed foods, and refined sugars. Even grain consumption wasn’t common until the Agricultural Revolution around 10,000 years ago, which is actually only around 5 percent of the human species’s existence.
Many tribal cultures today that maintain traditional hunter–gatherer diets are virtually free from metabolic syndrome, heart disease, and type 2 diabetes. For example, the Kitavan, Masai, Machiguenga, and !Kung consume very little, if any, refined grains or processed sugars, though the specific contents of their diets vary widely. (6, 7, 8, 9)
- Industrial seed oils have been shown to have a pro-inflammatory effect in some studies. (14)
- Processed grains and refined carbs cause both inflammation and metabolic dysfunction in mice, perhaps by disrupting the gut microbiota. (15)
- Excessive refined sugar intake, particularly high-fructose corn syrup, is correlated with insulin resistance and inflammation. (16, 17, 18)
Our modern diets are so detrimental to our health that when tribal cultures “Westernize” their diets, they quickly develop modern metabolic diseases. (19, 20, 21) They might be even more susceptible to modern diseases than those of European descent, who have thousands of years more evolutionary adaptation under their belts to accommodate grain consumption. Now, on the flip side, let’s see what happens when Western dieters revert to a Paleo, traditional diet.
Paleo Diets Outperform Other “Healthy” Diets
Paleo diets are finally appearing in randomized, controlled trials, to be compared to what are considered “healthy” or “heart-healthy” modern diets. Instead of focusing on macronutrients as most contemporary diet studies do, (22, 23, 24) these studies focused on avoiding or consuming different groups of foods all together, and the results are extremely promising. In the studies reviewed below, a Paleo diet was devoid of refined sugar, processed foods, vegetable oils, and grains, while also usually avoiding dairy and legumes. Favored foods included lean meats, vegetables, fish, eggs, fruit, and nuts.
Emerging research shows the Paleo diet outperforms “heart-healthy” diets.
Paleo diet is beneficial for people with type 2 diabetes
In a short, 14-day diet study, the Paleo diet was compared to the diet recommended by the American Diabetes Association in people with type 2 diabetes. (25) While both groups showed equivalent positive changes in weight and insulin sensitivity, only the Paleo group had beneficial changes in fasting glucose, total cholesterol, and LDL (“bad”) cholesterol.
In a longer, six-month crossover trial, the Paleo diet also outperformed the recommended diabetic diet. (26) In this sort of trial, half the participants started with the Paleo diet, and then switched to the Diabetic diet halfway through the study. The remaining participants did the the opposite. The Paleo diet showed greater improvements in triglycerides, HDL (“good”) cholesterol, diastolic blood pressure, body weight, and waist circumference.
In people with both insulin resistance and heart disease, a 12-week study showed that the Paleo diet resulted in more advantageous effects on both waist circumference and two-hour glucose measures than the popular Mediterranean diet. (27)
Paleo diet is beneficial for people with metabolic syndrome
In people who already had metabolic syndrome, the Paleo diet after only 14 days lowered blood pressure, cholesterol, and triglycerides, and raised HDL cholesterol better than the diet recommended by the Dutch Health Council. (28) In fact, the number of metabolic syndrome symptoms experienced by the Paleo group actually decreased over this short pilot study.
Over four months, people with hypercholesterolemia first followed the diet recommended by the American Heart Association and then followed with a Paleo diet. (29) The Paleo diet resulted in greater benefits for total cholesterol, LDL and HDL cholesterol, and triglycerides.
Two longer studies lasting two years compared the Paleo diet to modern “healthy” diets. In both cases, the Paleo diet outperformed the control diet at six months, but at the two-year mark, the diets showed mostly similar benefits. (30, 31)
Paleo diet is beneficial for healthy people
In otherwise healthy individuals, a Paleo diet improved body weight, waist circumference, and systolic blood pressure in three weeks. (32) Likewise, in non-obese yet sedentary people, a Paleo diet showed benefits for blood pressure, plasma insulin, total cholesterol, LDL cholesterol, and triglycerides. (33)
This growing collection of literature shows that reverting to a Paleo diet, even for as few as 14 days, can start to improve lipid markers and measures of metabolic syndrome. Research is finally catching up with what many people, myself included, have been advocating for a while: eat real, nutrient-dense foods, and you get healthier!
Why Does the Paleo Diet Get Such a Bad Rep?
U.S. News and World Report again ranked the Paleo diet near last, at 36 out of 38 diets in their “Best Diets Overall” rankings. Why might this be, especially since recent evidence highlights its health benefits?
Paleo dieters in controlled studies often consumed fewer calories ad libitum than dieters in the control groups, sometimes up to 35 percent fewer. (32) When Paleo groups show better health outcomes, critics ask, “Is it the Paleo diet itself or the fewer calories that is advantageous?” First, I fail to see how this can be considered a “negative” attribute of the Paleo diet. Spontaneous calorie restriction while feeling fuller calorie for calorie (34) sounds like the long-awaited solution to the current overeating epidemic. Second, many studies accounted for this extra weight loss. Boers et al., 2014, offered approved snacks to Paleo dieters. (28) At the end of the study, they still managed to lose more weight than the control group, but the researchers accounted for this in their statistical model and found the advantageous results remained, despite weight differences. Two other studies confirmed that the Paleo diet benefits remained after adjusting for weight loss or decreased waist circumference in the Paleo group. (27, 29)
Dieticians and nutritionists are also concerned with reduced calcium intake present in most Paleo diets. (26, 28, 32, 35) However, two studies reviewed above showed that while calcium intake was lower, calcium excretion was also lower, indicating that calcium absorption may be increased in Paleo dieters and/or that calcium/magnesium balance is probably not disrupted. (25, 28)
Last, the Paleo diet is ranked so low because it is considered hard to follow, with too many food restrictions. Yes, a Paleo diet is a commitment, but it is more than just a diet. Going Paleo is a lifestyle that should focus on many other aspects of health, including stress management, exercise, sleep, and reducing toxin exposure.
Adopt a Paleo Lifestyle, Transform Your Health
The Paleo diet has a lot to offer, whether you already have metabolic syndrome or if you are a healthy weight and have normal blood work. The research is finally in support of going Paleo, and hopefully more studies will follow with larger group sizes and longer follow-ups. If you are ready to transform your health, consider trying my 14Four program, which emphasizes four pillars of the Paleo lifestyle: movement, diet, stress, and sleep.
The 14Four program is perfect for beginners and for those who are already Paleo and just want a reset. With you every step of the way, this program eases you into the Paleo lifestyle with tailored meal plans and exercise routines, while tracking your results and offering community support.