Cheese consumption was not associated with adverse lipid profiles, measures of body fatness or other markers of metabolic health in this cohort, the authors concluded.
“What we saw was that in the high consumers [of cheese] they had a significantly higher intake of saturated fat than the non-consumers and the low consumers and yet there was no difference in their LDL Cholesterol levels,” said lead study author Dr Emma Feeney of the University College Dublin's (UCD) School of Agriculture and Food Science and Food for Health Ireland.
The researchers put forward the idea that differences in the calcium contents of different dairy products and differences in sphingolipid content could explain their observations.
The study also looked at dairy consumption as part of an overall dietary pattern that tracked participants’ dairy food intakes.
“We have to consider not just the nutrients themselves but also the matrix in which we are eating them in and what the overall dietary pattern is,” explained Dr Feeney.
“So not just about the food then, but the pattern of other foods we eat with them as well.”
Dr Feeney and her team collated results from a four-day food diary used to assess food and beverage consumption, including dairy (milk, cheese, yogurt, cream and butter) in healthy Irish adults aged 18–90 years. In total, 1,500 subjects took part.
Fasting blood samples (sample size, 897) were collected, and anthropometric measurements (BMI, waist-to-hip ratio, skin-fold test) were also taken.
Differences in metabolic health markers across patterns of dairy consumption were tested and patterns of dairy food consumption of different fat contents were identified using statistical analysis.
“Total dairy was associated with lower body mass index, percentage body fat, waist circumference and waist-to-hip ratio and lower systolic and diastolic blood pressure,” the study found. “Similar trends were observed when milk and yogurt intakes were considered separately.”
“Higher cheese consumption was also associated with higher C-peptide levels (a marker of inflammation).”
‘Blood lipid profiles are less favourable’
Three dairy consumption patterns were also identified in the study: 'Whole milk,' 'Reduced fat milks and yogurt' and 'Butter and cream.'
The 'Reduced fat milks and yogurt' eating pattern was found to have the highest scores on a Healthy Eating Index as well a lower-fat and saturated fat intake.
However, this group recorded greater triglyceride and total cholesterol blood levels.
“Overall, these results suggest that while milk and yogurt consumption is associated with a favourable body phenotype, the blood lipid profiles are less favourable when eaten as part of a low-fat high-carbohydrate dietary pattern.”
Dairy products, particularly higher-fat dairy products such as cheese, butter, cream and full-cream milk are considered significant sources of energy, and of saturated fat, contributing to around 20% of dietary saturated fat intakes in Ireland and the in UK.
The observations have to take into account the limitations of the study that may have had a bearing on the final results.
One negative aspect did not obtain fasting blood samples for every subject, which left a much smaller cohort of individuals in which to examine the biochemistry.
Another potential limitation, this time with the analysis, included percentage energy from trans-fat as one of the nine components without accounting for the food source of the fat.
“However, if anything, as dairy fat is a significant source of dietary trans-fat being able to account for the food source could have led to an even more positive outcome for the higher-fat dairy groups,” the study concluded.
Source: Nutrition and Diabetes
Published online ahead of print: doi:10.1038/nutd.2016.54
“Patterns of dairy food intake, body composition and markers of metabolic health in Ireland: results from the National Adult Nutrition Survey.”
Authors: E L Feeney, A O'Sullivan, A P Nugent, B McNulty, J Walton, A Flynn and E R Gibney