Paleolithic diets as a model for prevention and treatment of Western disease

Effects of a Paleolithic diet compared to a diabetes diet on leptin binding inhibition in secondary analysis of a randomised cross-over study

BACKGROUND

Beneficial effects from practising a Paleolithic diet as compared to a diabetes diet on weight, waist circumference, satiety, leptin, HbA1c and glucose control in randomised controlled trial participants with type 2 diabetes could be due to lower leptin resistance. Support for this hypothesis comes from an in vitro experiment that showed that digested wheat gluten, which is excluded from a Paleolithic diet, inhibits leptin from binding to its receptor, thus indicating a possible dietary cause of leptin resistance. However, the clinical relevance of the latter finding is unclear since removal of enzyme activity from the gluten digest by heat treatment also abolished leptin binding inhibition. Assessment of leptin binding inhibition in vivo is possible by comparison of total leptin levels with those of 'biologically active' leptin bound to its receptor (bioLep).

OBJECTIVES

To assess the effects of a Paleolithic diet compared to a diabetes diet on leptin binding inhibition and to replicate our in vitro study.

METHODS

BioLep and total leptin levels were measured in secondary analysis of fasting plasma samples from our open label random order three plus three-month long cross-over trial performed in 2005-2007, that compared a Paleolithic diet with a diabetes diet in participants with type 2 diabetes without insulin treatment (per protocol). BioLep was also measured in vitro for known recombinant leptin concentrations incubated with a series of concentrations of 10 kDa spin-filtered digested wheat gluten, with or without prior heat treatment, at 100ºC for 30 min and centrifugation.

RESULTS

There was no difference between diets when comparing differences between bioLep and total leptin levels and their ratio in the 13 participants, three women and 10 men, aged 52-74 years with a mean BMI of 30 kg/m2 and a mean diabetes duration of eight years. We found no carry-over or period effect for bioLep and total leptin. In vitro, wheat gluten digest inhibited leptin binding in a dose-dependent manner but not after heat treatment.

CONCLUSIONS

We found no leptin binding inhibition after the Paleolithic or diabetes diet, possibly due to its abolishment from cooking-related heat treatment of wheat gluten.

TRIAL REGISTRATION

Registered on 14/02/2007 at ClinicalTrials.gov Identifier: NCT00435240.

TFOS Lifestyle: Impact of nutrition on the ocular surface

Nutrients, required by human bodies to perform life-sustaining functions, are obtained from the diet. They are broadly classified into macronutrients (carbohydrates, lipids, and proteins), micronutrients (vitamins and minerals) and water. All nutrients serve as a source of energy, provide structural support to the body and/or regulate the chemical processes of the body. Food and drinks also consist of non-nutrients that may be beneficial (e.g., antioxidants) or harmful (e.g., dyes or preservatives added to processed foods) to the body and the ocular surface. There is also a complex interplay between systemic disorders and an individual's nutritional status. Changes in the gut microbiome may lead to alterations at the ocular surface. Poor nutrition may exacerbate select systemic conditions. Similarly, certain systemic conditions may affect the uptake, processing and distribution of nutrients by the body. These disorders may lead to deficiencies in micro- and macro-nutrients that are important in maintaining ocular surface health. Medications used to treat these conditions may also cause ocular surface changes. The prevalence of nutrition-related chronic diseases is climbing worldwide. This report sought to review the evidence supporting the impact of nutrition on the ocular surface, either directly or as a consequence of the chronic diseases that result. To address a key question, a systematic review investigated the effects of intentional food restriction on ocular surface health; of the 25 included studies, most investigated Ramadan fasting (56%), followed by bariatric surgery (16%), anorexia nervosa (16%), but none were judged to be of high quality, with no randomized-controlled trials.

Association of an evolutionary-concordance lifestyle pattern score with incident CVD among Black and White men and women

Dietary and lifestyle evolutionary discordance is hypothesised to play a role in the aetiology of CVD, including CHD and stroke. We aimed to investigate associations of a previously reported, total (dietary plus lifestyle) evolutionary-concordance (EC) pattern score with incident CVD, CHD and stroke. We used multivariable Cox proportional hazards regression to investigate associations of the EC score with CVD, CHD and stroke incidence among USA Black and White men and women ≥45 years old in the prospective REasons for Geographic and Racial Differences in Stroke study (2003-2017). The EC score comprised seven equally weighted components: a previously reported dietary EC score (using Block 98 FFQ data) and six lifestyle characteristics (alcohol intake, physical activity, sedentary behaviour, waist circumference, smoking history and social network size). A higher score indicates a more evolutionary-concordant dietary/lifestyle pattern. Of the 15 467 participants in the analytic cohort without a CVD diagnosis at baseline, 1563 were diagnosed with CVD (967 with CHD and 596 with stroke) during follow-up (median 11·0 years). Among participants in the highest relative to the lowest EC score quintile, the multivariable-adjusted hazards ratios and their 95 % CI for CVD, CHD and stroke were, respectively, 0·73 (0·62, 0·86; Ptrend < 0·001), 0·72 (0·59, 0·89; Ptrend < 0·001) and 0·76 (0·59, 0·98; Ptrend = 0·01). The results were similar by sex and race. Our findings support that a more evolutionary-concordant diet and lifestyle pattern may be associated with lower risk of CVD, CHD and stroke.

Nutrition Transition and Health Outcomes Among Indigenous Populations of Chile

BACKGROUND

Over the past several decades, rural and indigenous populations in Latin America have experienced abrupt and profound transformations in their lifestyles and economies, many having remarkable health consequences. Yet, these changes have had heterogeneous effects on the population's biology in different local contexts.

OBJECTIVES

The primary goal was to characterize the nutrition transition and biomarkers of noncommunicable diseases (NCD) risk in 2 Chilean indigenous populations that have had divergent histories of subsistence strategies (agropastoralism compared with hunter-gathering) in the last few millennia and live in contrasting environments, and to identify context-specific factors driving the nutrition and epidemiological transitions.

METHODS

One-hundred-and-ninety (90 Pehuenche and 100 Atacameño) participants aged 18-87 y completed demographic, food-frequency, and physical activity questionnaires as well as measurements of some NCD risk biomarkers: blood pressure, weight, height, body fat percentage, waist circumference, blood total cholesterol, HDL cholesterol, triglycerides, and glucose. Framingham risk scores (FRSs) were calculated based on age, sex, total cholesterol, HDL cholesterol, systolic blood pressure, smoking, diabetes status, and hypertension medication.

RESULTS

Few differences in dietary composition and physical activity patterns were observed between the 2 populations. Multivariate analyses showed no differences between the 2 populations in any of the individual NCD risk biomarkers or FRSs after adjusting for age, sex, time since last meal, food insecurity in childhood, ultraprocessed food consumption, and physical activity.

CONCLUSIONS

Despite contrasting ecological and historical contexts, the 2 groups are converging into similar processes of market and wage-labor integration and transitioning to a Western diet high in processed and nonlocal foods, although some aspects of their "traditional" foodways are still in practice. The frequency of individuals exhibiting NCD biomarkers "at-risk" is relatively high and corresponds to other populations that have gone through nutrition transition. Furthermore, none of these biomarkers or FRSs differed between the 2 populations, suggesting a homogenization in the NCD risk factors.

Perspective: Whole and Refined Grains and Health-Evidence Supporting "Make Half Your Grains Whole"

Research-based dietary guidelines suggest that consumers "make half their grains whole." Yet some advocate ingesting only whole-grain foods (WGFs) and avoiding all refined-grain foods (RGFs). Some even recommend avoiding all grain-based foods (GBFs). This article will provide arguments to counter negative deductions about GBFs and RGFs, especially staple ones, and to support dietary guidance recommending a balance of GBFs-achieved through the right mix, type, and quantity of WGFs and RGFs. Studies looking at early mortality, body weight, and glucose tolerance and diabetes will be used as examples to characterize the literature about GBFs. The following issues are highlighted: 1) inconsistent findings between epidemiological and interventional studies and impacts of GBFs on health outcomes, and the underreporting of findings showing RGFs neither raise nor lower health risks; 2) multiple confounding and potential interactions make adequate statistical adjustment difficult; 3) nonuniform WGF definitions among studies make comparison of results challenging, especially because some WGFs may contain 49-74% refined grain (RG); 4) binary categorization of GBFs creates bias because nearly all categories of WGFs are recommended, but nearly half the RGF categories are not; 5) ingestion of >5 (30-g) servings RGFs/d and <1 serving WFGs/d creates dietary imbalance; 6) pattern names (e.g., "white bread") may impugn RGFs, when names such as "unbalanced" or "few fruits and vegetables" may more fairly characterize the dietary imbalance; 7) avoidance of all enriched RGs may not only impair status of folate and other B vitamins and certain minerals such as iron and zinc but also decrease acceptability of WGFs; 8) extrapolation beyond median documented intakes in high-WGF consumers (∼48 g whole grain/d) in most cohorts is speculative; 9) recommended dietary patterns such as the Mediterranean diet demonstrate that the right mix of WGFs and RGFs contributes to positive health outcomes.

Palaeolithic Diet in Diabesity and Endocrinopathies - A Vegan's Perspective

Introduction: The Palaeolithic diet is designed to resemble that of human hunter-gatherer ancestors thousands to millions of years ago. This review summarises the evidence and clinical application of this diet in various disorders. An empiric vegan variant of it has been provided, keeping in mind vegan food habits. Review of the literature: different types of Palaeolithic diets in vogue include the 80/20, the autoimmune, the lacto, the Palaeolithic vegan and the Palaeolithic ketogenic. We have developed an Indian variant of the Palaeolithic vegan diet, which excludes all animal-based foods. The Palaeolithic diet typically has low carbohydrate and lean protein of 30–35% daily caloric intake in addition to a fibre diet from non-cereal, plant-based sources, up to 45–100 g daily. In different observational studies, beneficial effects on metabolic syndrome, blood pressure, glucose tolerance, insulin secretion, lipid profiles and cardiovascular risk factors have been documented with the Palaeolithic diet. Short-term randomised controlled trials have documented weight loss, and improved glycaemia and adipo-cytokine profiles. Few concerns of micronutrient deficiency (e.g. calcium) have been raised. Conclusion: Initial data are encouraging with regard to the use of the Palaeolithic diet in managing diabesity. There is an urgent need for large randomised controlled trials to evaluate the role of the Palaeolithic diet with different anti-diabetes medications for glycaemic control and the reversal of type 2 diabetes.

Dietary patterns and risk of cardiovascular diseases: a review of the evidence

CVD are the main cause of death especially in high-income countries. Previously, research focused on single nutrients including saturated and MUFA, sodium and dietary fibre, or specific foods such as fish, fruit and vegetables, and olive oil, in the aetiology of CVD. In recent years, however, the effects of complete dietary patterns on the prevention of CVD have gained interest, to account for diet heterogeneity and food–nutrient interactions. Several dietary patterns have been investigated, such as the Paleolithic diet, the vegetarian and vegan diets, the Diet Approaches to Stop Hypertension (DASH), the Nordic and Mediterranean diets, with many contradictions remaining. The aim of this review is to give an overview of the effects of these dietary patterns on CVD risk, to discuss their overall nutrient adequacy and briefly discuss their environmental impact.

A multidimensional measure of animal ethics orientation - Developed and applied to a representative sample of the Danish public

We present a questionnaire-based measure of four animal ethics orientations. The orientations, which were developed in light of existing empirical studies of attitudes to animal use and ethical theory, are: animal rights, anthropocentrism, lay utilitarianism, and animal protection. The two latter orientations can be viewed as variants of animal welfarism. Three studies were conducted in Denmark in order to identify the hypothesised orientations, evaluate their concurrent validity, and report their prevalence and relevance in animal-related opinion formation and behaviour. Explorative factor analysis (Study 1) and confirmative factor analysis (Study 2) successfully identified the four orientations. Study 2 revealed good measurement invariance, as there was none or very modest differential item functioning across age, gender, living area, and contrasting population segments. Evaluation of concurrent validity in Study 2 found that the orientations are associated with different kinds of behaviour and opinion when the human use of animals is involved in the hypothesised directions. In Study 3, a representative population study, the animal protection orientation proved to be most prevalent in the Danish population, and as in study 2 the four orientations were associated with different behaviours and opinions. Remarkably, the animal protection orientation does not lead to increased animal welfare-friendly meat consumption, the main reason for this being non-concern about the current welfare status of farm animals. We argue that the developed measure covers a wide range of diversity in animal ethics orientations that is likely to exist in a modern society such as Denmark and can be used in future studies to track changes in the orientations and to understand and test hypotheses about the sources and justifications of people’s animal-related opinions and behaviours.

The Evidence for Dietary Interventions and Nutritional Supplements as Treatment Options in Multiple Sclerosis: a Review

PURPOSE OF REVIEW

This review aims to critically evaluate published studies examining diets and nutritional supplements (excepting vitamin D) for the impact on prevention and prognosis of multiple sclerosis (MS).

RECENT FINDINGS

There is a negative relationship between the Mediterranean diet and vascular disease, and vascular co-morbidities are associated with a worse MS prognosis. Low-fat, fish-based diets, sodium-restricted diets, calorie restriction, the paleo diet, and gluten-free diets have been examined, mostly in observational studies; results are inconclusive. With regard to nutritional supplements, pilot data show a possible benefit of biotin with respect to disability worsening in people with progressive MS (PMS). The best designed randomized controlled trials (RCTs) for PUFA supplementation have not shown significant impact, but several weaker RCTs have. Many other nutritional supplements have been tested, including several anti-oxidants. While some early studies show positive results, no result has been definitive. Unfortunately, there is no strong evidence for a direct benefit of any given dietary intervention on MS risk or prognosis. However, due to its relationship with vascular co-morbidities, the Mediterranean diet has the strongest rationale for employment in PwMS. Higher-quality clinical trials are needed to ascertain the possible benefits of nutritional supplements.

A Paleolithic-type diet results in iodine deficiency: a 2-year randomized trial in postmenopausal obese women

BACKGROUND/OBJECTIVES

Different diets are used for weight loss. A Paleolithic-type diet (PD) has beneficial metabolic effects, but two of the largest iodine sources, table salt and dairy products, are excluded. The objectives of this study were to compare 24-h urinary iodine concentration (24-UIC) in subjects on PD with 24-UIC in subjects on a diet according to the Nordic Nutrition Recommendations (NNR) and to study if PD results in a higher risk of developing iodine deficiency (ID), than NNR diet.

SUBJECTS/METHODS

A 2-year prospective randomized trial in a tertiary referral center where healthy postmenopausal overweight or obese women were randomized to either PD (n=35) or NNR diet (n=35). Dietary iodine intake, 24-UIC, 24-h urinary iodine excretion (24-UIE), free thyroxin (FT4), free triiodothyronine (FT3) and thyrotropin (TSH) were measured at baseline, 6 and 24 months. Completeness of urine sampling was monitored by para-aminobenzoic acid and salt intake by urinary sodium.

RESULTS

At baseline, median 24-UIC (71.0 μg/l) and 24-UIE (134.0 μg/d) were similar in the PD and NNR groups. After 6 months, 24-UIC had decreased to 36.0 μg/l (P=0.001) and 24-UIE to 77.0 μg/d (P=0.001) in the PD group; in the NNR group, levels were unaltered. FT4, TSH and FT3 were similar in both groups, except for FT3 at 6 months being lower in PD than in NNR group.

CONCLUSIONS

A PD results in a higher risk of developing ID, than a diet according to the NNR. Therefore, we suggest iodine supplementation should be considered when on a PD.

Race and gender disparities in nutrient intake are not related to metabolic syndrome in 20- to 59-year-old US adults

BACKGROUND

The goal of this study was to examine the relationship between macronutrient and micronutrient intake and metabolic syndrome within race and gender cohorts of young US adults.

METHODS

The 2007-2010 National Health and Nutrition Examination Survey (NHANES) data for adults (n=2440) aged 20-59 were analyzed. Two 24-hr dietary recalls were used to measure intake of total calories, macronutrients, and 20 vitamins and minerals. Metabolic syndrome and its components were defined by the National Heart, Lung and Blood Institute criteria. Differences in statistical tests were noted when significant at P<0.05.

RESULTS

Prevalence of metabolic syndrome among 20- to 59-year-old adults was 30.4% [95% confidence interval 27.6-33.2]. Among cohorts, metabolic syndrome was highest in black women and white men, and lowest in black men and white women. Regression analysis indicated that no macronutrients were associated with greater risk of metabolic syndrome. For relative macronutrient intake, men with metabolic syndrome consumed more polyunsaturated fats, whereas women with metabolic syndrome consumed more total, saturated and monounsaturated fats and less fiber and starch than women without metabolic syndrome. Among races, white men and women consumed greater absolute quantities of all macronutrients except carbohydrates and sugar. Micronutrient intake was greatest for white men and women; women without metabolic syndrome had greater micronutrient adequacy than women with metabolic syndrome.

CONCLUSION

Nutrient intake varied between race/gender cohorts; however, there were few clinically significant differences in nutrient intake between those with and without metabolic syndrome. Diet may be marginally related to diagnosis of metabolic syndrome.

A healthy diet with and without cereal grains and dairy products in patients with type 2 diabetes: study protocol for a random-order cross-over pilot study--Alimentation and Diabetes in Lanzarote--ADILAN

Background

Research on the role of nutrition in type 2 diabetes has largely focused on macro/micronutrient composition and dietary fiber intake, while fewer studies have tested the effects of differing food choice. Some observational studies and short-term intervention studies suggest that a food pattern mimicking the diet with which humans evolved positively influences glucose control and associated endocrine systems. Such a food pattern mainly differs from other common healthy food patterns in its absence of cereal grains and dairy products. The primary aim of this pilot study is to determine the effect of two healthy diets with or without cereal grains and dairy products on glucose control, while keeping participants’ weight stable and other food parameters, such as macro/micronutrient composition, dietary fiber and glycemic load, the same in both diets.

Methods/Design

We intend to include 15 adult patients with a medical diagnosis of type 2 diabetes mellitus with or without medication and with an increased waist circumference (≥ 80 cm for women and ≥ 94 cm for men) in a random-order cross-over diet intervention study during two periods of four-weeks separated by a six-week washout period. Patients will be instructed to eat two healthy diets according to official dietary guidelines with respect to macro/micronutrient composition and fiber content, but differing in the type of food included, with one diet being without cereal grains and dairy products. Lunch will be served in a hospital kitchen for control of nutrient intake, while the rest of the meals will be eaten at home according to specific directions. The energy content of the diets will be individually adjusted to maintain a stable body weight during the two four-week intervention periods. Primary outcomes will be change in fasting plasma glucagon and fructosamine, while secondary outcomes include change in fasting glucose and glycated hemoglobin, glucose and glucagon response during oral glucose tolerance test, blood lipids, blood pressure, C-reactive protein, body composition, quality of life, subjective experience with the two diets, satiety scores and changes in medication.

Discussion

Using these results, we will assess the need to conduct larger and longer studies with similar design.

Trial registration

This trial was registered at clinicaltrials.gov as NCT01891955 and Spanish Agency of Medication and Sanitary Products (AEMPS) registration code: MFV-ADI-2013-01.

Metabolic effects of milk protein intake strongly depend on pre-existing metabolic and exercise status

Milk protein intake has recently been suggested to improve metabolic health. This Perspective provides evidence that metabolic effects of milk protein intake have to be regarded in the context of the individual’s pre-existing metabolic and exercise status. Milk proteins provide abundant branched-chain amino acids (BCAAs) and glutamine. Plasma BCAAs and glutamine are increased in obesity and insulin resistance, but decrease after gastric bypass surgery resulting in weight loss and improved insulin sensitivity. Milk protein consumption results in postprandial hyperinsulinemia in obese subjects, increases body weight of overweight adolescents and may thus deteriorate pre-existing metabolic disturbances of obese, insulin resistant individuals.

Intestinal microbiota, probiotics and mental health: from Metchnikoff to modern advances: part III - convergence toward clinical trials

Rapid scientific and technological advances have allowed for a more detailed understanding of the relevance of intestinal microbiota, and the entire body-wide microbiome, to human health and well-being. Rodent studies have provided suggestive evidence that probiotics (e.g. lactobacillus and bifidobacteria) can influence behavior. More importantly, emerging clinical studies indicate that the administration of beneficial microbes, via supplementation and/or fecal microbial transplant (FMT), can influence end-points related to mood state (glycemic control, oxidative status, uremic toxins), brain function (functional magnetic resonance imaging fMRI), and mental outlook (depression, anxiety). However, despite the advances in the area of gastro-biological psychiatry, it becomes clear that there remains an urgent need to explore the value of beneficial microbes in controlled clinical investigations. With the history explored in this series, it is fair to ask if we are now on the cusp of major clinical breakthroughs, or are we merely in the quicksand of Autointoxication II?

Plants, diet, and health

Chronic disease is a major social challenge of the twenty-first century. In this review, we examine the evidence for discordance between modern diets and those on which humankind evolved as the cause of the increasing incidence of chronic diseases, and the evidence supporting consumption of plant foods as a way to reduce the risk of chronic disease. We also examine the evidence for avoiding certain components of plant-based foods that are enriched in Western diets, and review the mechanisms by which different phytonutrients are thought to reduce the risk of chronic disease. This body of evidence strongly suggests that consuming more fruits and vegetables could contribute both to medical nutrition therapies, as part of a package of treatments for conditions like type 2 diabetes, heart disease, cancer, and obesity, and to the prevention of these diseases. Plant science should be directed toward improving the quality of plant-based foods by building on our improved understanding of the complex relationships between plants, our diet, and our health.

Comparison with ancestral diets suggests dense acellular carbohydrates promote an inflammatory microbiota, and may be the primary dietary cause of leptin resistance and obesity

A novel hypothesis of obesity is suggested by consideration of diet-related inflammation and evolutionary medicine. The obese homeostatically guard their elevated weight. In rodent models of high-fat diet-induced obesity, leptin resistance is seen initially at vagal afferents, blunting the actions of satiety mediators, then centrally, with gastrointestinal bacterial-triggered SOCS3 signaling implicated. In humans, dietary fat and fructose elevate systemic lipopolysaccharide, while dietary glucose also strongly activates SOCS3 signaling. Crucially however, in humans, low-carbohydrate diets spontaneously decrease weight in a way that low-fat diets do not. Furthermore, nutrition transition patterns and the health of those still eating diverse ancestral diets with abundant food suggest that neither glycemic index, altered fat, nor carbohydrate intake can be intrinsic causes of obesity, and that human energy homeostasis functions well without Westernized foods containing flours, sugar, and refined fats. Due to being made up of cells, virtually all "ancestral foods" have markedly lower carbohydrate densities than flour- and sugar-containing foods, a property quite independent of glycemic index. Thus the "forgotten organ" of the gastrointestinal microbiota is a prime candidate to be influenced by evolutionarily unprecedented postprandial luminal carbohydrate concentrations. The present hypothesis suggests that in parallel with the bacterial effects of sugars on dental and periodontal health, acellular flours, sugars, and processed foods produce an inflammatory microbiota via the upper gastrointestinal tract, with fat able to effect a "double hit" by increasing systemic absorption of lipopolysaccharide. This model is consistent with a broad spectrum of reported dietary phenomena. A diet of grain-free whole foods with carbohydrate from cellular tubers, leaves, and fruits may produce a gastrointestinal microbiota consistent with our evolutionary condition, potentially explaining the exceptional macronutrient-independent metabolic health of non-Westernized populations, and the apparent efficacy of the modern "Paleolithic" diet on satiety and metabolism.