Here is a collection of research articles regarding nutrition, health, obesity, and low-carb high-fat diets from peer-reviewed scientific journals, grouped by topic. For each article, I’ve included a short summary of the study’s main finding along with a link to the original paper.
These studies show that a diet low in carbohydrates and high in fat (or “LCHF,” like the ketogenic diet) is healthy with many benefits, leading to weight loss and cardiovascular benefits. This is in contrast to what many people unfortunately still believe — the incorrect assumption that eating fat makes you fat, despite extensive research attempting and failing to establish a relationship between fat consumption and obesity.
The emphasis on dietary fat reduction from public health officials and so-called health experts has been a very unfortunate distraction with serious consequences in efforts to control obesity and improve health in general.
The current obesity and health epidemic is due not only to diet but also to increased meal frequency and constant snacking. Accordingly, I have included several articles below regarding the health benefits of fasting. Intermittent fasting is an effective way to control insulin resistance and to lose weight.
Lastly, I’ve included some studies regarding low carb foods that are notable for their health benefits, including vinegar, chocolate, coffee, tea, and cinnamon. Many people ask about the healthiest sugar-free sweetener to use, so I have included research regarding my sweetener of choice, erythritol.
Hyde et al. 2019, JCI Insight, Dietary carbohydrate restriction improves metabolic syndrome independent of weight loss
Obese participants diagnosed with metabolic syndrome (linked to cardiovascular risk like heart disease and stroke) were given low/med/high carb diets. After 4 weeks, a low carb diet was found to be most effective at reversing metabolic syndrome, compared to moderate and high carb diets.
Athinarayanan et al. 2019, Front. Endocrinol., Long-Term Effects of a Novel Continuous Remote Care Intervention Including Nutritional Ketosis for the Management of Type 2 Diabetes: A 2-Year Non-randomized Clinical Trial
In a 2-year study of Type 2 diabetics, participants selected either a low carb diet (initially <30 g total carbs daily) or standard diabetes care. In the group with the low carb diet, half of them reversed their diabetes. The group with standard care did not experience diabetes reversal or improvement, and some participants worsened.
Gibas & Gibas 2017, Diabetes Metab Syndr, Induced and controlled dietary ketosis as a regulator of obesity and metabolic syndrome pathologies
From a study of 30 adults over 10 weeks, a keto diet with no exercise out-performs a standard American diet with exercise in terms of weight, body fat percentage, BMI, and hemoglobin A1c.
El-Rashidy et al. 2017, Metab Brain Dis, Ketogenic diet versus gluten free casein free diet in autistic children: a case-control study
Autistic children received either a keto diet, a gluten-free dairy-free diet, or a balanced nutrition diet (control group). After 6 months, both diet groups showed significant improvement in autism rating scales and evaluation tests, with the keto group scoring even better in cognition and sociability compared to the gluten-free dairy-free group.
Bazzano et al. 2014, Ann Intern Med, Effects of Low-Carbohydrate and Low-Fat Diets: A Randomized Trial
Nearly 150 men and women without cardiovascular disease or diabetes participated in either a low-fat or low-carb diet. The low carb diet was more effective for weight loss and cardiovascular risk factor reduction than the low fat diet.
Foster et al. 2010, Ann Intern Med, Weight and metabolic outcomes after 2 years on a low-carbohydrate versus low-fat diet: a randomized trial
Patients were treated with a low fat or low carb diet for 2 years. The low carb patients had more favorable changes in cardiovascular disease risk factors.
Shai et al. 2008, N Engl J Med, Weight Loss with a Low-Carbohydrate, Mediterranean, or Low-Fat Diet
A 2-year study of obese women shows that the low carb diet is more effective in weight loss compared to both the mediterranean diet and low fat diet.
Samaha et al. 2003, N Engl J Med, A Low-Carbohydrate as Compared with a Low-Fat Diet in Severe Obesity
Severely obese people have greater weight loss while on a low carb diet compared to a calorie-restricted, low-fat diet. While on a low carb diet, subjects improved in glycemic control, had no adverse effects on blood lipid levels, and had lowered triglyceride levels which is indicative of a cardiovascular benefit.
Low Carb, High Fat
Ebbeling et al. 2018, BMJ, Effects of a low carbohydrate diet on energy expenditure during weight loss maintenance: randomized trial
Weight gain after weight loss is thought to be due to decreased energy expenditure. Lowering carbohydrate intake increased energy expenditure during weight loss maintenance, which may increase the chances of successful obesity treatment.
Gregory et al. 2017, Int J Sports Exerc Med, A Low-Carbohydrate Ketogenic Diet Combined with 6-Weeks of Crossfit Training Improves Body Composition and Performance
Subjects following a low carb ketogenic diet and CrossFit training saw decreases in their body fat percentage, fat mass, and BMI while maintaining their lean body mass. They also had improvements in their performance power and time.
Chen et al. 2016, Eur Journal Nutr, Cheese consumption and risk of cardiovascular disease: a meta-analysis of prospective studies
Cheese contains a high level of saturated fatty acids, so an analysis was performed to determine how long-term cheese consumption affected cardiovascular disease. This analysis was based off of 15 studies that showed higher cheese consumption is associated with a lower risk of cardiovascular disease.
Kratz et al. 2013, Eur J Nutr, The relationship between high-fat dairy consumption and obesity, cardiovascular, and metabolic disease
From a review of 16 studies covering the relationship between dairy fat consumption, obesity, and heart disease, they found no evidence that dairy fat contributes to obesity or cardiometabolic risk. In fact, these studies suggest that high fat dairy consumption is inversely associated with obesity risk.
Friedman et al. 2012, Clin J Am Soc Nephrol, Comparative effects of low-carbohydrate high-protein versus low-fat diets on the kidney
A low carb diet over 2 years is not linked to harmful effects related to kidney functions.
Boden et al. 2005, Ann Intern Med, Effect of a low-carbohydrate diet on appetite, blood glucose levels, and insulin resistance in obese patients with type 2 diabetes
Obese patients with type 2 diabetes were given a low carb diet and after 14 days, patients had significantly improved blood glucose profiles and insulin sensitivity as well as decrease triglyceride and cholesterol levels.
Leosdottir et al. 2005, J Intern Med, Dietary fat intake and early mortality patterns–data from The Malmö Diet and Cancer Study
In a study including nearly 30,000 people over 5 years, those who ate more than 30% of their daily diet in fat did not have increased mortality, so dietary recommendations regarding fat intake are not supported by these results.
Dashti et al. 2004, Exp Clin Cardiol, Long-term effects of a ketogenic diet in obese patients
Obese patients were subjected to a 24-week ketogenic diet. After the study, patients had significantly decreased weight and body mass index, decreased total cholesterol, increased HDL cholesterol, decreased LDL cholesterol, decreased triglycerides, and decreased blood glucose. There were no significant side effects.
Gillman et al. 1997, JAMA, Inverse association of dietary fat with development of ischemic stroke in men
A study of over 800 middle-aged men during 20 years of followup shows that dietary intake of fat, saturated fat, and monounsaturated fat are associated with lower risk of stroke.
Carbs & Sugar
Ginieis et al. 2018, Phys Beh, The “sweet” effect: Comparative assessments of dietary sugars on cognitive performance
A double-blind, placebo-controlled study of 49 people shows that consuming sucrose (sugar) and glucose leads to poorer performance on cognitive tasks such as simple response time and arithmetic.
Zheng et al. 2018, Diabetologia, HbA1c, diabetes and cognitive decline: the English Longitudinal Study of Ageing
From a study of 5189 subjects over 10 years, people with high blood sugar have a faster rate of cognitive decline including dementia than those with normal blood sugar, regardless if they are diabetic or not. The higher the blood sugar, the faster the cognitive decline.
Kearns et al. 2017, PLoS Biol, Sugar industry sponsorship of germ-free rodent studies linking sucrose to hyperlipidemia and cancer: An historical analysis of internal documents
The sugar industry secretly funded a study in 1965 to evaluate sugar’s effect on cardiovascular health. When the results suggested that sugar was harmful, they buried the data.
DiNicolantonio & O’Keefe 2017, Open Heart, J Markedly increased intake of refined carbohydrates and sugar is associated with the rise of coronary heart disease and diabetes among the Alaskan Inuit
Analysis of the Alaskan Inuit diet shows that higher consumption of carbs and sugar is linked to the rise of coronary heart disease and diabetes.
Grasgruber et al. 2016, Food Nutr Resesarch, Food consumption and the actual statistics of cardiovascular diseases: an epidemiological comparison of 42 European countries
From a study of relationships between nutritional factors and the prevalence of cardiovascular diseases in Europe, the major correlate of high cardiovascular disease risk was the proportion of dietary energy from carbs and alcohol, or potatoes and cereal carbs. Even unrefined cereals have high insulin indices.
Basu et al. 2013, Plos One, The Relationship of Sugar to Population-Level Diabetes Prevalence: An Econometric Analysis of Repeated Cross-Sectional Data
By studying food and diabetes prevalence in 175 countries, it was found that for every 150 kcal/person/day increase in sugar availability (about 1 can of soda each day), it was associated with an increase in diabetes prevalence of about 1%.
Tsai et al. 2005, Gut, Dietary carbohydrates and glycaemic load and the incidence of symptomatic gall stone disease in men
From a study with 12 years of follow up, results suggest that high carb consumption increases the risk of gall stone disease in men.
Gardener et al. 2012, J Gen Intern Med, Diet soft drink consumption is associated with an increased risk of vascular events in the Northern Manhattan Study
Daily consumption of diet soft drinks are linked to an increased risk for stroke and other vascular events.
Dhingra et al. 2007, Circulation, Soft drink consumption and risk of developing cardiometabolic risk factors and the metabolic syndrome in middle-aged adults in the community
Among middle aged adults, soft drink consumption is associated with higher incidence of cardiometabolic risk factors.
Schulze et al. 2004, JAMA, Sugar-sweetened beverages, weight gain, and incidence of type 2 diabetes in young and middle-aged women
Sugary beverages are linked to weight gain and increase in type 2 diabetes in women.
Stanhope et al. 2009, J Clin Invest, Consuming fructose-sweetened, not glucose-sweetened, beverages increases visceral adiposity and lipids and decreases insulin sensitivity in overweight/obese humans
Both glucose and fructose consumption contribute to weight gain, but fructose causes significantly higher cholesterol concentrations and reduces sensitivity to insulin.
Nielsen et al. 1980, Am J Clin Nutr, Impaired cellular insulin binding and insulin sensitivity induced by high-fructose feeding in normal subjects
Young healthy subjects were fed usual diets plus either glucose or fructose. After one week, the group with fructose feeding had a significant reduction in their insulin binding and insulin sensitivity, whereas the glucose group had no significant change. Fructose rather than glucose is responsible for the insulin binding/sensitivity issue in sucrose.
Fruits & Vegetables
Kaiser et al. 2014, Am J Clin Nutr, Increased fruit and vegetable intake has no discernible effect on weight loss: a systematic review and meta-analysis
Health experts often recommend eating more fruits and vegetables to lose weight. A review of two studies showed that increased fruit and vegetable consumption does not cause weight loss.
Howard et al. 2006, JAMA, Low-fat dietary pattern and risk of cardiovascular disease: the Women’s Health Initiative Randomized Controlled Dietary Modification Trial
A study of nearly 50,000 women over 8 years showed that a diet low in fat and high in vegetables, fruits, and grains did not reduce the risk of cardiovascular disease, stroke, and coronary heart disease.
Koopman et al. 2014, Hepatology, Hypercaloric diets with increased meal frequency, but not meal size, increase intrahepatic triglycerides: a randomized controlled trial
High meal frequency increases abdominal fat, but increasing meal size does not, which suggests that frequent snacking leads to obesity.
Leidy et al. 2010, Obesity, The influence of higher protein intake and greater eating frequency on appetite control in overweight and obese men
In a study of obese men, satiety and fullness-related responses were greater on a higher protein diet but lower when they increased their eating frequency. This challenges the idea that increasing the number of eating occasions increases satiety.
Cameron et al. 2010, Br J Nutr, Increased meal frequency does not promote greater weight loss in subjects who were prescribed an 8-week equi-energetic energy-restricted diet
Increasing meal frequency does not help promote greater weight loss.
Kinouchi et al. 2018, Cell Reports, Fasting Imparts a Switch to Alternative Daily Pathways in Liver and Muscle
Fasting affects circadian clocks in the liver and skeletal muscle, which impacts their metabolism. This can lead to improved protection against aging-related diseases.
Alirezaei et al. 2010, Autophagy, Short-term fasting induces profound neuronal autophagy
Short term fasts (24-48 hours) produce a therapeutic neuronal response in the brain.
Bhutani et al. 2010, Obesity, Improvements in coronary heart disease risk indicators by alternate-day fasting involve adipose tissue modulations
Obese subjects were studied over 10 weeks with an alternate-day fasting diet. At the end of the trial, their fat mass decreased, their LDL cholesterol was 25% lower, and their waist circumference was reduced.
Lamine et al. 2006, Tunis Med, Food intake and high density lipoprotein cholesterol levels changes during ramadan fasting in healthy young subjects
Analyzing young adults who fast during the month of Ramadan (abstaining from food and drink each day from dawn to sunset), their blood lipoprotein metabolism improved with an increase of HDL cholesterol. This increase was lost after Ramadan.
Johnstone et al. 2002, Int J Obes Relat Metab Disord, Effect of an acute fast on energy compensation and feeding behaviour in lean men and women
A study of healthy men and women on a 36 hour fast did not lead to a stimulus to compensate after the fast.
Stewart & Fleming 1973, Postgrad Med J, Features of a successful therapeutic fast of 382 days’ duration
An old paper, but one of my favorites. A 27-year-old 456-pound man fasted for 382 days under doctor supervision, losing 276 pounds or 0.72 pounds/day, with no ill effects.
Storey et al. 2007, Eur J Clin Nutr, Gastrointestinal tolerance of erythritol and xylitol ingested in a liquid
Erythritol causes significantly less intestinal distress than xylitol.
Dean et al. 1996, Regul Toxicol Pharmacol., Chronic (1-year) oral toxicity study of erythritol in dogs
Erythritol (up to 3.5 g/kg body wt.) is well-tolerated in dogs over a 1 year period. No diarrhea, and no observed changes in body weight, plasma electrolyte concentrations, kidneys, organs, or tissues.
Noda et al. 1994, Eur J Clin Nutr, Serum glucose and insulin levels and erythritol balance after oral administration of erythritol in healthy subjects
Erythritol does not affect blood levels of glucose or insulin. More than 90% of the ingested erythritol is readily absorbed and excreted in the urine.
Kawanabe et al. 1992, Caries Res, Noncariogenicity of Erythritol as a Substrate
Erythritol is a promising sugar substitute from a dental point of view, as researchers found that it resulted in significantly less dental decay compared to sucrose (table sugar).
Greenberg & Geliebter 2012, J Am Coll Nutr, Coffee, hunger, and peptide YY
A study of healthy men shows that decaf coffee decreases hunger and increases the satiety hormone.
Huxley et al. 2009, Arch Intern Med, Coffee, decaffeinated coffee, and tea consumption in relation to incident type 2 diabetes mellitus: a systematic review with meta-analysis
High intakes of coffee, decaf coffee, and tea are linked to lower risk of diabetes.
van Dieren et al. 2009, Diabetologia, Coffee and tea consumption and risk of type 2 diabetes
Coffee and tea consumption is associated with a reduced risk of type 2 diabetes, which cannot be explained by magnesium, potassium, caffeine, or blood pressure effects.
Djousse et al. 2011, Clin Nutr, Chocolate consumption is inversely associated with prevalent coronary heart disease: the National Heart, Lung, and Blood Institute Family Heart Study
Dark chocolate consumption is inversely related to coronary heart disease in the U.S. population.
Grassi et al. 2005, Hypertension, Cocoa reduces blood pressure and insulin resistance and improves endothelium-dependent vasodilation in hypertensives
Consumption of dark chocolate decreases blood pressure, insulin resistance, and may provide some cardiovascular benefits.
Jiang et al. 2017, Metabolism, Cinnamaldehyde induces fat cell-autonomous thermogenesis and metabolic reprogramming
Human fat cells exposed to cinnamaldehyde, a compound in cinnamon, undergo thermogenesis, a process where the cells burn fat for energy.
Hlebowicz et al. 2007, Am J Clin Nutr, Effect of cinnamon on postprandial blood glucose, gastric emptying, and satiety in healthy subjects
Cinnamon consumption reduces blood glucose but has no significant effect on satiety.
Schulze et al. 2004, Am J Clin Nutr, Glycemic index, glycemic load, and dietary fiber intake and incidence of type 2 diabetes in younger and middle-aged women
From a study of over 90,000 women over 8 years, higher glycemic index foods are associated with an increased risk of diabetes, but fiber intake is associated with a decreased risk.
Chandalia et al. 2000, N Engl J Med, Beneficial Effects of High Dietary Fiber Intake in Patients with Type 2 Diabetes Mellitus
Thirteen patients with type 2 diabetes followed either a moderate fiber diet (24 g) or a high fiber diet (50 g). Both diets were prepared in a research kitchen with the same macro and energy content. The patients on the high fiber diet had reduced total cholesterol concentrations by 6.7%, triglyceride concentrations by 10.2%, and lipoprotein cholesterol concentrations by 12.5%.
Barbanti et al. 2017, Neurological Sciences, Ketogenic diet in migraine: rationale, findings and perspectives
Reviewing clinical data from 150 patients in case reports and studies, it is possible that a keto diet is effective for episodic and chronic migraines. A keto diet would help restore brain excitability and metabolism, and to counter neuroinflammation. Precise mechanism is not clear. Paper includes a nice table of previous literature results.
Di Lorenzo et al. 2013, Funct Neurol., Diet transiently improves migraine in two twin sisters: possible role of ketogenesis?
A pair of twin sisters had high-frequency migraines, which improved during a keto diet that they followed in order to lose weight.
Hirsso et al. 2006, Cent Eur J Public Health, Association of insulin resistance linked diseases and hair loss in elderly men. Finnish population-based study
From a study of 245 Finnish men at age 63, male pattern baldness was found to be common, but associated with insulin resistance related issues such as diabetes and hypertension. Rate of diabetes was almost twice as much in men with hair loss.
Matilainen et al. 2003, J Cardiovasc Risk, Hair loss, insulin resistance, and heredity in middle-aged women. A population-based study
From a study of 324 women at age 63, those with hair loss had significantly higher insulin resistance related parameters like waist/neck circumferences, waist-to-hip ratio, and insulin concentration compared to those with normal hair or very minimal hair loss.
Harvey et al. 2018, J Nutr Metab., The Effect of Medium Chain Triglycerides on Time to Nutritional Ketosis and Symptoms of Keto-Induction in Healthy Adults: A Randomised Controlled Clinical Trial
Healthy adults starting a keto diet were given MCTs (medium chain triglycerides) or sunflower oil as a control group. The MCT group had a higher level of blood ketones at all times, but unclear whether it resulted in a faster time to nutritional ketosis compared to the control group. Keto induction symptoms were higher for the control group, except for abdominal pain in the MCT group.
Islami et al. 2017, CA Cancer J Clin, Proportion and number of cancer cases and deaths attributable to potentially modifiable risk factors in the United States
Nearly half of all incident cancers and cancer deaths in 2014 were due to unhealthy and preventable behavior: cigarette smoking (29% cancer deaths), excess body weight (7%), and alcohol intake (4%).
Sabate & Wien 2010, Asia Pac J Clin Nutr, Nuts, blood lipids and cardiovascular disease
Examining data from large epidemiological studies across two continents, an 8% reduction in risk of death from coronary heart disease was found for each weekly serving of nuts. Intake of nuts lowers total and LDL cholesterol.
White & Johnston 2007, Diabetes Care, Vinegar Ingestion at Bedtime Moderates Waking Glucose Concentrations in Adults With Well-Controlled Type 2 Diabetes
Drinking 2 tablespoons of apple cider vinegar at bedtime moderates the next morning’s fasting glucose concentration for those with type 2 diabetes.
Fernandez 2006, Curr Opin Nutr Metab Care, Dietary cholesterol provided by eggs and plasma lipoproteins in healthy populations
Egg consumption does not lead to higher risk of developing coronary heart disease, but in fact has multiple beneficial effects.
Must et al. 1992, N Engl J Med, Long-term morbidity and mortality of overweight adolescents. A follow-up of the Harvard Growth Study of 1922 to 1935
An overweight adolescent is significantly more likely to have an increased risk of mortality from all causes and diseases, no matter the adult weight after 55 years of follow-up. In particular, colorectal cancer and gout among men, arthritis among women, and coronary heart disease among both groups. Being overweight in adolescence is a more accurate predictor of these risks than being overweight as an adult.