Research Studies

Two men lived on an exclusive meat diet for 1 year and a third man for 10 days. The relative amounts of lean and fat, meat ingested were left to the instinctive choice of the individuals. At the end of the year, the subjects were mentally alert, physically active, and showed no specific physical changes in any system of the body. Vitamin deficiencies did not appear. Kidney function tests revealed no evidence of kidney damage. In these trained subjects, the clinical observations and laboratory studies gave no evidence that any ill effects had occurred from the prolonged use of the exclusive meat diet.
 

In 2017, the World Health Organization (WHO) reported that mental illness was the leading cause of disability worldwide. They estimated that over 300 million people suffer from depression and over 260 million people suffer from anxiety. These estimates reflect a substantial increase in the number of people living with mental disorders over the past two decades... In parallel with increments in mental disorders, vegetarianism and veganism have become more popular and prevalent worldwide.. As a result, the question of whether meat consumption or avoidance is associated with better mental health has become a controversial issue in public health and nutrition science... Briefly, we found that the majority of studies showed that meat abstainers (vegetarians and vegans) had substantially higher rates or risk of depression, anxiety, and/or self-harm. Additionally, these groups were more likely to be prescribed medication for mental-health issues.

This bogus study is discussed here: 
https://carnivoretalk.com/topic/74-the-red-meat-diabetes-harvard-study/
There are so many holes and errors with this study. 
 

Migraine is the second world’s cause of disability. Among non-pharmacological treatments, nutritional intervention, particularly ketogenic diet, represents one of the most promising approaches.

"Reduction of total cholesterol (TC) has been an integral part of public health campaigns... 
Although disease-specific morbidity and mortality, such as IHD mortality, have their analytical merits, all-cause mortality is arguably the most important endpoint for patients or the general population when assessing risk factors and the effectiveness of a treatment or a public health intervention for life-threatening diseases. The target TC levels for public health interventions in the general population should be determined after careful consideration of the levels associated with the lowest mortality in the general population...
Through a large prospective cohort study among over 12 million participants, we examined whether the association between TC levels and all-cause mortality varied by sex and age, and estimated the sex- and age-specific levels of TC associated with the lowest mortality. Additionally, detailed estimates of the mean (and median) concentrations of TC according to sex and age are presented."

In 2020 a team of researchers at Harvard University conducted the first mainstream study on the carnivore diet.  The study surveyed over 2000 carnivore dieters. The findings were published in Current Developments in Nutrition, Volume 5, Issue 12 in December 2021.

Meat intake, not carbohydrate crops, is the significant predictor of life expectancy.
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