Tag Archives: paleolithic diet

Paleolithic Diet Improved Metabolic Syndrome in Just Two Weeks

Wish I were here

Wish I were here

A Paleolithic-type diet over two weeks improves several heart disease risk factors in folks with metabolic syndrome, according to Netherlands-based researchers.

The investigators wondered if the paleo diet, independent of weight loss, would alter characteristics of the metabolic syndrome. They seem to be the first scientists to do a study like this.

“Metabolic syndrome” may be a new term for you. It’s a collection of clinical features that are associated with increased future risk of type 2 diabetes and atherosclerotic complications such as heart attack and stroke. One in six Americans has metabolic syndrome, including almost one in four of adults. The most common definition of metabolic syndrome (and there are others) is the presence of at least three of the following characteristics:

  • high blood pressure (130/85 or higher, or using a high blood pressure medication)
  • low HDL cholesterol: under 40 mg/dl (1.03 mmol/l) in a man, under 50 mg/dl (1.28 mmol/l) in a women (or either sex taking a cholesterol-lowering drug)
  • triglycerides over 150 mg/dl (1.70 mmol/l) (or taking a triglyceride-lowering drug)
  • abdominal fat: waist circumference 40 inches (102 cm) or greater in a man, 35 inches (88 cm) or greater in a woman
  • fasting blood glucose over 100 mg/dl (5.55 mmol/l)

These five criteria were identical to the ones used in the study at hand. But the study participants were required to have only two of the five, not three, for unclear reasons. I found no consensus definition elsewhere that would define metabolic syndrome as only two of the five conditions. Study participants ate either a paleo-style diet or a reference/control diet. Those eating the reference diet didn’t quite have the metabolic syndrome since they had a mean (“average”) of 2.7 metabolic syndrome characteristics. The paleo group had 3.7 characteristics.

How Was the Study Done?

Average age of the 34 study participants was 53 and they were generally healthy. None had diabetes, cardiovascular disease, or systolic pressure over 180 mmHg. Smokers were excluded. Mean body mass index was 32 (obese). Only 9 of the 34 subjects were men. Subjects were randomized to either a Paleolithic-type diet (n=18) or a “healthy reference diet based on the guidelines of the Dutch Health Council” (n=14). Efforts were made to keep body weight stable during the two-week study. Participants were nearly all caucasian.

All meals were home-delivered free of charge by a catering service.

The Paleolithic-type diet “…was based on lean meat, fish, fruit, leafy and cruciferous vegetables, root vegetables, eggs and nuts. Dairy products, cereal grains, legumes, refined fats, extra salt and sugar were not part of it.” [I like their version of the paleo diet.] Protein supplied 24% of calories while carbohydrate was 32% and fat 41%.

You can consult the full text of the published article for details of the Dutch Health Council diet. Calories were 17% from protein, 50% from carbohydrate, and 29% from fat. Alcohol isn’t mentioned at all.

Despite randomization, the paleo diet group had more metabolic syndrome characteristics than the reference diet group. For instance, 78% of the paleo group had elevated fasting glucose compared to 44% of the reference group. And 67% of the paleo group had low HDL cholesterol compared to just 13% of the reference group. These glucose and HDL differences were statistically significant. 39% of the paleo had high triglycerides compared to 19% of the others. Furthermore, the paleos’ average body weight was 98 kg (216 lb) compared to 86 kg (189 lb) in the others. The paleo group had 3.7 characteristics of the metabolic syndrome versus 2.7 in the other cohort.

Go John trail at Cave Creek Regional Park in Scottsdale, Arizona

Go John trail at Cave Creek Regional Park in Scottsdale, Arizona


Compared to the reference diet, the paleo-style diet:

  • lowered systolic pressure by 9 points and diastolic by 5
  • total cholesterol fell by 0.52 mmol/l (20 mg/dl)
  • triglycerides fell by 0.89 mmol/l (79 mg/dl)
  • HDL cholesterol (good) rose by 0.15 mmol/l (6 mg/dl)
  • body weight fell by 1.32 kg (3 lb)
  • one metabolic syndrome characteristic resolved

No significant changes were seen in intestinal permeability ( by differential sugar absorption test on urine), salivary cortisol, and inflammation (hsCRP, TNFα).

Fasting plasma insulin and HOMA-IR fell in the paleo group but not the other.[Good news for folks with diabetes or prediabetes.] Yet the authors write, “Regarding glucose intolerance we did not find significant changes in our study.”

Fasting blood glucose for the group as a whole at baseline was about 1o8 mg/dl (6.0 mmol/l). Fasting glucose fell in both groups: 16 mg/dl (0.9 mmol/l) in the paleo group, 6 mg/dl (0.35 mmol/l) in the other. This was not a statistically significant difference between the groups. These numbers are from the text of the report; looking at the tables, I calculate different and less impressive reductions. The falls in fasting glucose from baseline were statistically significant for both diets.

Nearly all the statistical analysis focused on comparing the paleo diet group to the reference diet group.

My Comments

Overall, I’m not very pleased with this study. My biggest problems are 1) the unfortunate randomization that created dissimilar experimental groups,  2) the use of two diet protocols, 3) some of the study participants didn’t even have metabolic syndrome, and 4) as is typical for paleo diet studies, not many experimental subjects were involved.

The randomization led to significant differences in the metabolic syndrome patients in the two diet groups. I’m puzzled why the authors don’t comment on this. It’s a problem with clinical studies involving low numbers of participants. Ideally, you want to apply the two different diets to groups of people that are as similar as possible. These groups weren’t that similar.

The investigators’ main goal was to study whether a paleo-style diet, independent of weight loss, alters characteristics of the metabolic syndrome. Then why introduce another variable, the Dutch Health Council diet? Is it the gold standard for treating metabolic syndrome? Has it even been used to treat metabolic syndrome? The authors don’t tell us. And why not restrict participation to subjects who meet the common international definition of metabolic syndrome (at least three of the five characteristics)? Why not just take all your subjects and switch them from their standard Netherlands diet to the paleo diet? That would increase your statistical power, and would have avoided the randomization mis-match in which some in the reference diet group didn’t even have metabolic syndrome.

Here we’ve got two different experimental groups, and we’re applying a different diet to each group. The results are going to be messy and difficult to interpret. It’s always better if you can alter just one variable.

Since the paleo and reference diet cohorts were so different at baseline, why not make it easy to simply compare the paleo diet group’s “before and after numbers”? Maybe the analysis is there and I’m just not smart enough to see it.

There weren’t enough men in the study to tell us anything about the paleo diet in men with metabolic syndrome.

The statistical analysis was difficult for me to read and understand. There’s a good chance I’ve missed or misinterpreted something.

This paleo diet reduced fasting blood sugar significantly, making me think it may help in management of diabetes and prediabetes.

I estimate that as much as a quarter of the experimental subjects didn’t even have metabolic syndrome, so the study title is a bit of a misnomer.

This paleo diet did result in resolution of one metabolic syndrome characteristic, which is a good thing. So you could say the diet improves metabolic syndrome, even resolves it in some folks if it drops their metabolic syndrome characteristics from three to two. It predominantly helps lower blood pressure and triglycerides, and reduces excess weight modestly. In white women. Compared to the healthy Dutch Health Council diet.

If I had metabolic syndrome, I’d do something about it in hopes of lowering my future risk of diabetes and atherosclerotic complications. Standard physician advice is to lose excess weight and exercise regularly. There’s no consensus on diet yet. I think carbohydrate restriction is important. If the study at hand is reproducible in a larger study population, the paleo diet is a reasonable approach. Dietitian Franziska Spritzler has a great review of nutritional management of metabolic syndrome at her blog. The Mediterranean diet supplemented with nuts helps improve metabolic syndrome. The Spanish Ketogenic Mediterranean Diet may cure metabolic syndrome.

Steve Parker, M.D.

Update: I took a fresh look at this study as if it were simply a paleo diet trial involving 18 subjects who had metabolic syndrome. If I’m interpreting Table 5 correctly, and I think I am, these are the statistically significant changes after two weeks:

  • abdominal circumference decreased by 3.1 cm
  • systolic and diastolic blood pressures dropped by 8.5 and 8, respectively
  • fasting glucose dropped by 0.4 mmol/l (7 mg/dl)
  • fasting insulin fell
  • HOMA-IR decreased (less insulin resistance)
  • total cholesterol decreased from 220 to 193 mg/dl (5.7 to 5.0 mmol/l)
  • LDL-cholesterol decreased from 135 to 124 mg/dl (3.5 to 3.2 mmol/l)
  • triglycerides decreased from 168 to 89 mg/dl (1.9 to 1.0 mmol/l)

HDL cholesterol was unchanged.

The fall in AUC (area under the curve) for insulin approached but didn’t reach statistical significance (p=0.08)

Body weight fell from 98 kg (216 lb) to 95.3 kg (210 lb) but I found no p value. HDL-cholesterol was unchanged (the higher HDL I mentioned above is only in comparison to the reference diet, in which HDL fell)

All of these changes (except the lack of change in HDL-chol) would tend to promote health in someone with metabolic syndrome, prediabetes, or overweight type 2 diabetes.

Reference: Boers, Inga, et al. Favorable effects of  consuming a Palaeolithic-type diet on characteristics of the metabolic syndrome: a randomized controlled pilot-studyLipids in Health and Disease. 2014 Oct 11;13:160. doi: 10.1186/1476-511X-13-160.

Ever Heard of Paleolithic Diet Pioneer Arnold De Vries?

paleo diet, Paleolithic diet, hunter-gatherer diet

Not Arnold Paul De Vries or Don Wiss, but a Huaorani hunter in Ecuador

Don Wiss turned me on to another “modern” paleo diet pioneer, Arnold Paul De Vries, who wrote a 1952 book called Primitive Man and His Food. I even found the book on the Internet a few months ago, perhaps in violation of copyright. I can’t find it now. You can request a digital copy of the book here.

I read his thoughts on the diets of North American Indians before my other duties interrupted me.

Steve Parker, M.D.

Reference (see Comments)

Evolutionary Aspects of Obesity, Insulin Resistance, and Cardiovascular Risk

paleo diet, Paleolithic diet, hunter-gatherer diet

Huaorani hunter in Ecuador

Spreadbury and Samis have a review-type article in Current Cardiovascular Risk Reports. Here’s the abstract:

Cardiovascular disease (CVD) is still virtually absent in those rare populations with minimal Western dietary influence. To date, exercise, altered fats, fibre, anti-oxidants or Mediterranean diet do not appear to overcome the discrepancy in CVD between hunter-gatherer and Western populations. The CVD risk factors of obesity and diabetes are driven by increased caloric intake, with carbohydrates potentially implicated. Paradoxically, non-Westernized diets vary widely in macronutrients, glycemic and insulinemic indices, yet apparently produce no obesity or CVD regardless, even with abundant food. ‘Ancestral’ grain-free whole-food diet may represent the best lifestyle intervention for obesity and CVD. Such diets are composed of the cells of living organisms, while Western grains, flour and sugar are dense, acellular powders. Bacterial inflammation of the small intestine and vagal afferents appears a crucial step in leptin-resistance and obesity. Therefore it may be important that the Western diet resembles a bacterial growth medium.

You may remember Spreadbury’s name from his theory about acellular carbohydrates causing obesity via alterations in gut microorganisms. Spreadbury is with the Gastrointestinal Diseases Research Unit, Queen’s University, Kingston, Ontario, Canada.

You can read the articles for yourself. The following are a few of the authors points I found interesting or want to remember.

Does physical activity explain differences in CVD between Westernized and non-Westernized Peoples? They say “maybe.”

Throughout the article are references to aboriginals like the Hadza, Kitavans, Ache, Shuar, Australian aborigines, and Inuits. I always take comparisons of them to modern Europeans with a grain of salt, because of potential genetic differences between the populations. Moreover, diet and activity levels are only two of myriad cultural differences.

Australian Aborigine in Swamp Darwin

Australian Aborigine in Swamp Darwin

Can dietary changes reduce the incidence of CVD? They say it’s unclear.

Regarding modern paleo diet trials, “All the studies with ad libitum eating [eat all you want] have reported a spontaneous reduction in caloric intake in the order of 15-30%.” (Three references.) “The reduced food intake appeared driven by a satiety increase that was apparently not explicable by energy density, fiber or macronutrient content.” (One reference.)

“In those eating a Westernized diet, carbohydrates are increasingly recognized as being associated with poor metabolic health.” Evidence? Only one reference cited: Zienczuk’s 2012 article on high arctic Inuits.

“…non-Westernized populations with excellent metabolic and cardiovascular health almost invariably have negligible dietary contribution from grains, as well as refined sugar.” No citations.

“For ‘western-style’ diets and most obesogenic diets tested, gut microbiota appear to play a crucial role in obesity.” That’s a bold statement. References? Only one, a mouse study.

The rest of the article is about Spreadbury’s acellular carb/obesity theory. He suggests that small intestine bacteria play a more prominent role than colonic germs. Bacterial-driven inflammation….

The authors provide an example of a grain-free whole-food diet. It’s unrestricted in fruit, leafy or root vegetables, unprocessed meats, eggs, fish, nuts (except peanuts), mushrooms, herbs and spices. Occasional foods to be eaten in moderation are legumes, rice, yogurt, milk, cheeses, sweet corn, palm oil/lard/olive oil, and salt. Avoid almost all processed foods, breads, cereals, cakes/cookies/donuts etc., refined sugars, dried or processed fruits, vegetable/seed oils, and processed meats. They advise a vitamin D supplement. I’m not sure if they came up with this diet on their own, or it’s S. Lindeberg’s outline.

A final quote:

The macronutrient independence of the health from ancestral diet suggests whole foods are more important to health than their macronutrient or other chemical components, and that good health is associated with unprocessed cellular foods. Flour, sugar and processed foods appear to be important drivers of Western metabolic dysfunction, overweight and inflammation, and may prove to have a profound impact on, or even be the initiators of cardiovascular disease.

I’m sure Spreadbury and Samis would agree we need more basic science and clinical research into these issues, involving human test subjects. Maybe I’m prejudiced, but I’m more interested in Asians, Africans, and Europeans than Shuar people.

Steve Parker, M.D.

Reference: Spreadbury, Ian and Samis, Andrew J.S. Evolutionary aspects of obesity, insulin resistance, and cardiovascular risk. Current Cardiovascular Risk Reports, April 2013, vol. 7, issue 2, pp. 136-146.

Another Paleo Diet Success Story For a Type 1 Diabetic

The Joslin Diabetes Blog has details. Lindsay Swanson was diagnosed with type 1 diabetes at age 25. Her initial interest was spurred by years of undiagnosed gastrointestinal issues. She eased into the Paleolithic diet by sequentially eliminating certain food classes, starting with grains, then soy, then legumes. As she did, she felt increasingly better. Lindsay eats few refined carbohydrates. My sense is she doesn’t require much insulin. A quote:

Much to my surprise, my blood sugars completely leveled out, so much so that I rarely need to treat a low blood sugar, and spikes are few and far between….Probably 75 percent of my diet consists of vegetables and plant based food, some with more carbohydrates depending on my activity level. I eat a lot of fat/protein regularly, examples: avocados, coconut oil (in tea and cooking), grassfed meats, bacon (and the reserved fat), oils, nuts, etc.


Another Review Article In Favor Of Paleolithic Eating

It’s in the Annual Review of Plant Biology. The authors promote fruit and vegetable consumption. A snippet from the 2013 article:

Our Paleolithic ancestors were hunter-gatherers, consuming diets rich in lean wild meat or fish, with relatively high consumption of fruits and green leafy vegetables. Our modern diets, in contrast, are high in saturated fats and starches, added sugars with high energy load, and “unnatural fats” such as transfats. Paleolithic diets, in contrast to those of simians and present-day hunter-gatherers, are estimated to have been approximately 75% fruit [that’s news to me; reference is from S. Lindeberg]. In modern US diets, foods unavailable to Paleolithic societies—including dairy products, cereal grains, refined cereal flour, refined sugars, refined vegetable oils, and alcohol—on average make up 70% of total energy consumption. Of this, 50% is in the form of vegetable oils and refined sugars .Americans currently consume less than 60% of the US Department of Agriculture recommendations for vegetables and less than 50% of the recommendations for fruits.

h/t Bill Lagakos

Reference: Annu. Rev. Plant Biol. 2013. 64:19–46. This article’s doi:10.1146/annurev-arplant-050312-120142

Recipe: Waldorfian Salad

paleobetic diet, low-carb diet

One cup of Waldorfian salad. I doubled the cinnamon in this batch, so yours won’t look quite like this.

Today’s meal is inspired by the classic Waldorf salad, made famous by New York’s Waldorf Hotel over a century ago. The hotel today is called the Waldorf-Astoria.

The primary ingredients are apples, walnuts, and celery.

The original salad was made with mayonnaise, which I’m leaving out since I don’t yet have a paleo-compliant formula. They’re out there, however. Do you have a favorite?

paleobetic diet

Good source of omega-3 fatty acids

Instead of mayonnaise, we use a dressing—a vinaigrette—made with walnut oil. Walnut oil is attractive in part because it is rich in omega-3 fatty acids: 1.77 grams per tbsp (15 ml). Compared with Paleolithic diets, modern Western diets are too low in omega-3s and too high in omega-6s. You can use your left-over walnut oil the way you’d use olive oil.

paleobetic diet, low-carb diet, ketogenic diet

I made my dressing in this BPA-laden plastic container

In composing the Paleobetic Diet, my biggest challenge is breakfast. I’m fine eating eggs almost daily, but that may not be your cup ‘o tea. Most of us in America are accustomed to grain-based options like cold cereal, porridge, bagels, donuts, pancakes, granola, and toast. Plus yogurt. Those aren’t paleo, and they have too many carbohydrates for many diabetics. I came up with Waldorfian salad as a low-carb paleo-style breakfast, reminiscent of Brian’s Berry Breakfast.

This recipe makes two large servings of 2 cups (480 ml) each. Small or sedentary folks may well be satisfied with a 1- or 1.5-cup serving.

paleobetic diet, low-carb diet, ketogenic diet

Apples are the primary source of carbohydrates in this recipe.


2 apples, raw, medium size, skin on, diced (I used Red Delicious; consider Granny Smith, Fuji, or Gala)

3 celery stalks, 8-inches long (20 cm), diced

1 cup (240 ml) walnuts, broken by hand into small chunks (Option for ? more flavor: toast in a skillet over medium-high heat for 7-10 minutes or in oven (350 F or 175 C) on baking sheet for 10 minutes

1/4 tsp (1.2 ml) black pepper, ground

1/4 tsp (1.2 ml) salt

1.5 tbsp (22 ml) walnut oil

1 tbsp (15 ml) cider vinegar

1/2 tsp (2.5 ml) cinnamon

1/4 tsp (1.2 ml) nutmeg


First make a dressing with the bottom six ingredients. I put mine in a small container with a lid, then shook vigorously. Or you can put them in a small bowel and whisk them.

paleobetic diet, low-carb diet, ketogenic diet

Walnut pieces

Place the walnuts, apples and celery in a bowel, add the dressing and toss thoroughly. You’re done.

Serve as is, or chill first in the refrigerator. Maybe it was my imagination, but I thought it tasted better after it sat on the counter for 10 minutes. Consider serving on a bed of lettuce (1-2 oz), but if you do, increase your digestible carb count by 1-2 grams.

If you want more calories or protein than this recipe provides, chicken or steak should go well with Waldorfian salad and won’t increase your carb grams.

Number of Servings: 2 (2 cups each)

Nutritional Analysis:

73% fat

21% carbohydrate

6% protein

500 calories

27.5 g carbohydrate

7.6 g fiber

20 g digestible carbohydrate

341 mg sodium

529 mg potassium

Prominent features: High in copper and manganese, low in sodium. This is vegetarian (so much for the paleo diet being meat-centric). On a 2,000 calorie diet, this provides only 15% of the Recommended Dietary Allowance for protein, so you’ll want to eat more protein at some point during the day.

Free Online Paleo Recipes

Sirloin steak, salad, cantaloupe, 3 raspberries

Sirloin steak, salad, cantaloupe, raspberries (on the Paleobetic Diet)

Or paleo-ish anyway.

Most diabetics eating paleo-style need to know how may grams of digestible carbohydrate they’re eating. Their blood sugars will go too high if they eat too many carbs. “Too many” varies from one person to another. Additional nutrient numbers are just icing on the cake. (Oops! Not a good metaphor for a Stone Age diet website.) Other than this site, I’ve only found three other sites that divulge basic nutritional analysis of their free recipes. Several sites listed are primarily low-carb, so you have to see if the recipe you’re interested in fits your definition of paleo.

Before you go, I just want you to consider financially supporting the owners and writers at the following sites. Many of them have books or services for sale. Some have a Donate button. If they can’t bring home the bacon, the websites go down and the recipes go bye-bye.

Recipes With Nutritional Analysis

Catalyst Athletics

Linda’s Low-Carb Recipes

Hold the Toast (I bet Dana Carpender’s “500 Paleo Recipes” book provides basic nutrient analysis.)

Paleo Diabetic

More Recipes (You can do your own nutritional analysis at places like Fitday.)

The Clothes Make the Girl

NomNom Paleo

The Paleo Diet

Julianne’s Paleo & Zone Nutrition (see drop-down menu under Paleo Links, Recipes, and Meals tab)

Everyday Paleo (see drop-down menu under Food tab)

Paleo Food

Paleo Plan


Perfect Health Diet

Diabetes Warrior

Whole Life Eating

Nell Stephenson

Paleo Diet Lifestyle

Happy hunting!

Steve Parker, M.D.

Ryberg et al: Effects of Paleolithic Diet on Obese Postmenopausal Women

Sweden's Flag. Most of the researchers involved with this study are in Sweden

Sweden’s Flag

After menopause, body fat in women tends to accumulate more centrally than peripherally. This is reflected in a higher incidence of fatty liver disease, type 2 diabetes, and cardiovascular disease. A multinational group of researchers wondered if a modified paleo-style diet would have metabolic effects on healthy overweight and obese (BMI 28–35) postmenopausal women in Sweden, with particular attention to fat levels in liver and muscle. I’ll call this the Ryberg study because that’s the first named author.

Study Details

Curiously, they never give the age range of the 10 study participants. Were they closer to 52 or 82?

tuna, fishing, Steve Parker MD, paleo diet, tuna salad

Has anyone even bothered to ask why the tuna are eating mercury? —Jim Gaffigan

The five-week intervention diet seems to have been mostly prepared and provided by the investigators, but they allowed for home cooking by providing menus, recipes, and a food list. No limit on consumption. The goal was to obtain 30% of calories from protein, 40% from fat (mostly unsaturated), and 30% from carbohydrate “…together with 40 g nuts (walnuts and sweet almonds) on a daily basis….”

The diet included lean meat, fish, fruit, vegetables (including root vegetables), eggs and nuts. Dairy products, cereals, beans, refined fats and sugar, added salt, bakery products and soft drinks were excluded.

“They were also advised to use only rapeseed [i.e., canola] or olive oil in food preparation.”

A diet like this should reduce average saturated fat consumption, which was a stated goal, while substituting monounsaturated  and polyunsaturated fat for saturated.

These women were sedentary before and during the intervention.


The ladies indeed made some major changes in their diet. Total calories consumed fell by 22% (2,400 to 1,900 cals). The average weight of participants dropped from 190 lb (86.4 kg) to 180 lb (81.8 kg).

Carbohydrates consumption as a percentage of total calories fell from 49% to 25%. Total carb  grams dropped from 281 to 118, with fiber grams unchanged. To replace some of the carbs, the women increased their protein and fat calorie percentages by about a third. The authors don’t make it clear whether the total carb grams included total fiber grams. (I could probably figure it out if I had the time and inclination, but don’t.) “Before” and “after” fiber grams were 25 and 27, respectively.

In other words, “…the ratio between energy intake from the macronutrients protein, total fat and carbohydrates expressed as E% [calorie percentages] changed significantly from 16:33:50 at baseline to 28:44:25 after five weeks.” Total daily fat grams didn’t change, but the contribution of saturated fat grams fell.

Elevated blood pressure is one component of metabolic syndrome

Elevated blood pressure is one component of metabolic syndrome

A 10-point drop in systolic blood pressure over the five weeks didn’t quite reach statistical significance (p=0.057), but the 9% drop in diastolic pressure did.

“Fasting serum levels of glucose, leptin, cholesterol, triglycerides, HDL, LDL, ApoB and apolipoprotein A1 (ApoA1) and percentage HDL also decreased significantly.”

Fat (or lipid) content of the liver dropped by half. It was measured by magnetic resonance spectroscopy. Peripheral muscle fat content didn’t change, measured in the soleus and  tibialis anterior muscles of the leg.

Urinary C-peptide excretion and HOMA indices [HOMA1-IR formula] decreased significantly, whereas whole-body insulin sensitivity, measured using the hyperinsulinaemic euglycaemic clamp technique, was not significantly changed.” See footnote labelled PPS at bottom page for confusing details.

My Comments

The intervention diet was a reasonable version of the Paleolithic diet, with one exception. From what I’ve seen from Eaton, Konner, and Cordain, I think they’d agree. Except for the rapeseed oil. It’s fallen out of favor, hasn’t it?

Here’s what the Jaminet’s wrote about canola:

Canola oil…is rapeseed oil bred and processed to remove erucic acid and glucosinolates. During processing, the oil is treated with the solvent hexane and very high temperatures; it may also be subject to caustic refinement, bleaching, and degumming. [Perfect Health Diet, p.225.]

I can’t quite see Grok doing that.

My fantasy about extra virgin olive oil is that it simply oozes out of the olives when pressure is applied. So easy a caveman could do it.

Eaton and Konner have argued that our ancestral diet would have had at least two or three times the fiber as was provided by this diet. But that would have been at a total daily calorie consumption level of at least 3,000 or 3,5oo back in the day. So this diet isn’t so far off.

10-lb Weight Loss Without Calorie Restriction? I'll Take That.

10-lb weight loss In five weeks without conscious calorie restriction? I’ll take that.

The 10 lb (4.6 kg) weight loss is impressive for an eat-all-you-want diet. Calorie intake dropped spontaneously by 500/day, assuming the numbers are accurate. The satiation from higher protein consumption may explain that. The authors admit that the women lost more weight than would be predicted by the energy balance equation (i.e., a pound of fat = 3,500 calories). They wonder about over-estimations of food intake, thermogenic effects of protein versus other macronutrients,  and loss of glycogen (and associated body water). You can’t argue with those scales, though.

While serum C-peptide didn’t fall, urinary levels did. (My sense from reviewing other literature is that 24-hr urine levels of C-peptide are more accurate indicators of insulin production, compared to a single fasting C-peptide level.) The authors interpret this as increased insulin sensitivity in the liver in combination with decreased insulin secretion by the pancreas. Fasting serum insulin levels fell from 8.35 to 6.75 mIU/l (p<0.05).

Regarding the non-significant change in overall insulin sensitivity as judged by hyperinsulinemic euglycemic clamp technique, remember that insulin sensitivity of the liver may be different from sensitivity in peripheral tissues such as muscle. These investigators think that liver insulin sensitivity was clearly improved with their diet.

Blood lipid changes were in the right direction in terms of cardiovascular disease risk, except for the drops in HDL (from 1.35 to 1.17 mmol/l) and ApoA1.

This study may or may not apply to men. Also note the small sample size. Will these results be reproducible in a larger population? In different ethnicities?

I like the reduction in blood pressure. That could help you avoid the risk, expense, and hassle of drug therapy.

From 97 to 90 mg/dl

Serum glucose fell from 96  to 90 mg/dl

I like the drop in fasting blood sugar from 96 to 90 mg/dl (5.35 to 5 mmol/l). It’s modest, but statistically significant. Was it caused by the weight loss, reduced total carb consumption, paucity of sugar and refined starches, lower total calories, higher consumption of protein and mono- and polyunsaturated fats, or a combination of factors? As with most nutritional studies, there’s a lot going on here. A small fasting blood sugar drop like this wouldn’t matter to most type 2 diabetics, but could diabetics see an even greater reduction than these non-diabetics? Only one way to tell: do the study.

I can well imagine this diet curing some cases of metabolic syndrome, prediabetes, mild type 2 diabetes, and fatty liver disease.

Most type 2 diabetics (and prediabetics, for that matter) are overweight or obese.  If a diet like this helps them lose weight, it could improve blood sugar levels. Nearly all authorities recommend that overweight and obese diabetics and prediabetics get their weight down to normal. (I admit that weight loss and improved blood sugar levels are not always in sync.) Weight loss by any standard method tends to improve insulin sensitivity.

Furthermore, the elevated fasting blood sugars that characterize so many cases of diabetes and prediabetes are usually linked to, if not caused by, insulin resistance in the liver. According to these investigators, the diet at hand improves insulin sensitivity in the liver, and even lowers fasting blood sugars in non-diabetic older women.

This modified Paleolithic-style diet doesn’t include table sugar or refined grain starches. That would help control blood sugar levels in both type 1 and type 2 diabetics and prediabetics. The authors didn’t say so, but this must be a relatively low-glcemic-index diet.

The investigators don’t mention ramifications of their diet for folks with diabetes. Their focus is on ectopic fat accumulation (in liver and muscle) and its linkage with insulin resistance and cardiovascular disease. They’ve put together a promising program to try on diabetics or prediabetics. They just need the will and funding to git’r done.

I agree with the authors that the lower calorie consumption, rather than the paleo diet per se, may have caused or contributed to the reduction in liver fat.

Stockholm Palace

Stockholm Palace

The investigators wonder if a Paleolithic-style diet like this would be beneficial over the long-term in patients with non-alcoholic fatty liver disease (NALFD) and associated metabolic disturbance (e.g., impaired sensitivity sensitivity in the liver). NAFLD tends to predict the development of diabetes and cardiovascular disease. If we can prevent or reverse fatty liver, we may prevent or reverse type 2 diabetes and cardiovascular disease, to an extent. You’ll be waiting many years for those clinical study results.

But you have to decide what to eat today.

A significant number of American women (20%?) need to lose weight, lower their blood pressures, lower their blood sugars, and decrease their liver fat. This Ryberg Paleolithic-style diet would probably do it.

A very-low-carb diet is another way to reduce liver fat, and it’s more effective than simple calorie restriction.

Steve Parker, M.D.

Reference: Ryberg, M., et al. A Palaeolithic-type diet causes strong tissue-specific effects on ectopic fat deposition in obese postmenopausal women. Journal of Internal Medicine, 2013, vol. 274(1), pp: 67-76.  doi: 10.1111/joim.12048

PS: See Carbsane Evelyn for her take on this study here and here.

PPS: Urinary C-peptide secretion reflects insulin production. HOMA is a gauge of insulin resistance, much cheaper and quicker than the purported “gold-standard” hyperinsulinemic euglycemic clamp technique. Why HOMA and the clamp technique in this study didn’t move together is unclear to me, and the authors didn’t explain it. School me in the comment section if you can. Click this HOMA link and you’ll find this statement: “HOMA and clamps yield steady-state measures of insulin secretion and insulin sensitivity in the basal and maximally stimulated states, respectively. HOMA measures basal function at the nadir of the dose-response curve, whereas clamps are an assessment of the stimulated extreme.” Maybe that means HOMA is applicable to the fasted state (no food for 8 hours), whereas the clamp technique is more applicable to the hour or two after you ate half a dozen donuts.

History of the “Modern” Paleo Diet Movement

Here’s a timeline, certainly not comprehensive, but probably more than enough to bore you. I’m trying to hit the major developments.

  • 1939 – Nutrition and Physical Degeneration by Weston A. Price’s is published.
  • 1973 – Stephen Boyden’s “Evolution and Health” is published in The Ecologist.
  • 1975 – The Stone Age Diet: Based On In-Depth Studies of Human ecology and the Diet of Man is self-published by Walter L. Voegtlin, M.D.
  • January 1985 – “Paleolithic Nutrition. A consideration of its nature and current implications” by S. Boyd Eaton and M. Konner in the New England Journal of Medicine.
  • 1987 – Stone Age Diet by Leon Chaitow (London: Optima).
  • 1988 – The Paleolithic Prescription: A Program of Diet and Exercise and a Design for Living by S. Boyd Eaton, M. Shostak, and M. Konner.
  • January 1997 – Paleodiet.com established by Don Wiss.
  • March 1997 – The Paleodiet listserv established by Dean Esmay and Donn Wiss.
  • April 1997 – The Evolutionary Fitness online discussion list is created. Art DeVany is its anchor and Tamir Katz is a regular participant.
  • April 1997 – Jack Challem published the article “Paleolithic Nutrition: Your Future Is In Your Dietary Past.”
  • 1999 – Neanderthin by Ray Audette is published.
  • November 2001 – Evfit.com established by Keith Thomas (“Health and Fitness in an Evolutionary Context”).
  • December 2001 – The Paleo Diet by Loren Cordain, Ph.D., is published.
  • April 2001 – Wikipedia’s page on Palaeolithic diet is created.
  • 2005 – Art DeVany’s first paleo blog.
  • 2006 – Exuberant Animal by Frank Forencich is published.
  • 2008 – Art DeVany’s Las Vegas seminar.
  • 2009 – The Primal Blueprint by Mark Sisson is published. Art DeVany announces ‘The New Evolution Diet’.
  • 8 January 2010 – The New York Times features the paleo lifestyle in its ‘fashion’ pages.
  • 26 February 2010 – McLean’s (Canada) publishes a general audience review of the paleo movement.
  • February 2010 – Food and Western Disease by Staffan Lindeberg is published.
  • March 2010 – Paleolithic lifestyle page is created on Wikipedia.
  • September 2010 – The Paleo Solution: The Original Human Diet by Robb Wolf is published.

Contributors to this timeline include Keith Thomas, Paul Jaminet, and Ray Audette (the latter two via blog comments). Any errors are mine.

Of the folks above, my major influences have been Cordain, Eaton, and Konner.

What would you add? I’m tempted to include the Jaminet’s book (Perfect Health Diet) and Dr. Emily Deans’ blog. Paul Jaminet mentioned Jan Kwasniewski’s Optimal Diet of 1990 (or was it Optimal Nutrition?), but is that just “the Polish Atkins,” as some say? Very high fat.


Is the Paleo Diet Truly Low-Carb After All?

Lifextension argues that very case in a recent blog post. If the paleo diet is low carb, then it’s going to be heavily animal-based. According to Lifextension:

Diachronic and comparative analysis of the skeletal data of human hunters and cultivators from across the globe has revealed that – prior to the onset of agriculture – carbohydrates must have comprised only a rare and occasional component of ancestral eating patterns. Furthermore, the impact of the introduction of carbohydrates to human diets was almost immediate in its deterioration of human health and biology.

However, paradoxically, many proponents of a ‘Paleo’ (i.e.: pre-agricultural) diet have promoted the use of tubers and other starches as – not only benign – but necessary health foods to consume for the correction of metabolic and endocrine disorders. Potatoes, rice, and other oxymoronically-labelled ‘safe’ starches, are being promoted in spite of the fact that they are exclusively Neolithic foods. Consequently, it is the conflation of starches, safe, and ancestral that I now wish to address, and hopefully correct.

Lifextension concludes:

The intake of plant foods by hominids was most plausibly and conceivably minimal. This is due to their limited, seasonal availability; the physiological ceiling on fibre and toxin intake; the biological evolution of early Homo physiology; along with the technological, spatial and temporal limitations of obligatory pre-consumption preparations. Consequently, evolutionary arguments for the consumption of what are quite blatantly Neolithic foods are rendered paradoxical and absurd. Starches are neither ‘Paleo’; nor does our evolutionary biology sanction them as ‘safe’.

Lifextension neither pulls punches nor takes prisoners. This could get interesting.

Read the rest.