A diet that includes a lot of protein, whole grains and vegetables can help you get through the year, but it can also lead to an increased risk of heart disease, type 2 diabetes and a higher risk of certain cancers.
The study, published in the New England Journal of Medicine, analysed data from the National Health and Nutrition Examination Survey (NHANES) between 1994 and 2012, which measured diet, health and well-being.
It also analysed data on food intake and physical activity.
The researchers analysed data for 5.4 million adults aged 25 and over.
The average daily intake of protein was 5.9 grams per person, with an average of 4.5 grams for men and 3.5 for women.
The highest level of protein intake was found in the top 10% of the food group, with a mean intake of 6.6 grams.
The food group with the highest level in terms of total protein intake, the researchers said, was nuts and seeds.
“There are many reasons for this, but a significant factor is that nut and seed intake tends to be higher in the western world than in other parts of the world,” Dr John Sacks, lead author of the study from the University of Cambridge, said.
“In contrast, the protein intake of people in the tropics tends to tend to be lower than that of the rest of the population, which in turn makes the consumption of nuts and seed appear to be beneficial in terms to weight loss.”
Dr Sacks said he was surprised to find that the highest protein intake in the food groups was in the highest income group.
“These findings should be interpreted with caution, as the study is cross-sectional and there is an inherent risk of bias from missing information,” he said.
The average amount of physical activity, which was found to be highest in the lowest income groups, was just 2.9 minutes per week.
This may sound like a lot, but the researchers say that physical activity is probably not the main factor that is linked to a lower risk of cardiovascular disease and diabetes.
“The researchers found that the association between high levels of physical inactivity and the risk of diabetes was strongest in the subgroups of the participants with low physical activity,” the researchers wrote.
“Thus, in this study, physical activity was not associated with a lower incidence of cardiovascular diseases or type 2 diabetic nephropathy.”
The authors said they would like to see more studies of different groups of people to see if the findings apply to other groups.
“This is one of the first longitudinal studies to examine the relationship between diet and health in a cohort of UK adults,” Dr Sacks added.
“If this association holds up over time, we would hope that diet can be an important part of prevention strategies for preventing or managing diabetes.”
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