Disease occurrence And Inflammation in relation to Raw cow*s milk consumption in elderlY people.

The global incidence of asthma, inflammation-related and autoimmune diseases is
rising sharply. Milk and dairy-based products have been shown to have
beneficial effects on the levels of pro-inflammatory mediators, and inverse
associations have been described between dairy consumption and risk of
inflammation-related diseases, such as type 2 diabetes, colorectal cancer, and
Alzheimer*s disease. More specifically, evidence suggests early-life exposure
to raw cow*s milk contributes to protection against allergies, asthma, and
respiratory tract infections. Raw cow*s milk is suggested to contain
immunomodulating food allergens and bacteria that are otherwise destroyed or
altered by processing of milk. Evidence on the association between raw cow*s
milk consumption and immunity is restricted to early-life exposure. Due to its
microbiological hazard, raw cow*s milk consumption is not recommended. It is
estimated that 30% of dairy farmers does drink raw cow*s milk on a regular
basis, making them a suitable study population to study the association between
raw milk consumption and the occurrence of various diseases. To be able to
conduct a future RCT, observational data as well as data on the difference and
variance of inflammatory markers in those with high versus low raw cow*s milk
consumption is required. This essential information will be gathered in the
current study.

The main aim of the proposed study is to 1) assess the habitual consumption of
raw cow*s milk among a large population of adult dairy farmers; 2) assess the
association between raw cow*s milk consumption and inflammation-related,
auto-immune and infectious disease prevalence and incidence, and 3) explore the
differences and associated variances in the age-related inflammatory markers
IL-6, CRP, and sVCAM in serum between elderly dairy farmers that consume raw
cow*s milk versus those that consume ultra-high-temperature (UHT)-processed
cow*s milk instead. If a link between raw cow*s milk consumption and
inflammation exists, novel dietary strategies based on minimal processing of
milk may become reality and will contribute to reduce the burden of
inflammation-related, auto-immune, and infectious diseases.

This study will consist of a prospective cohort study with baseline
cross-sectional data and a feasibility study for a future RCT study to enable
the design of a randomized controlled trial evaluating the effect of minimally
processed cow*s milk consumption on inflammatory markers. From the almost
18.000 dairy farmers associated with Friesland Campina, participants will be
recruited for the cohort study, in which they are asked to fill out several
questionnaires assessing habitual dietary intake, disease prevalence, drug use,
history of education, smoking status, and physical activity. For the
prospective study, subjects will be asked to fill out the questionnaires every
2 years, with a total follow-up for at least 10 years.

While recruiting participants for the cohort study, 60 elderly subjects will be
recruited living in the vicinity of Wageningen for the feasibility study: 30
consumers of raw cow*s milk and 30 consumers of UHT-processed cow*s milk.
Thirty ml of blood will be drawn. Levels of the inflammatory markers IL-6, CRP,
and sVCAM will be analysed and compared between groups.

Funding is currently available for recruitment, baseline assessments and
cross-sectional data-analyses of the cohort study and recruitment, blood
collection, assessment of serum levels of IL-6, CRP and sVCAM of the 60 elderly
farmers recruited for the feasibility study. For follow-up of the cohort and,
ultimately, for conducting an RCT with minimally processed cow*s milk,
additional funding will be sought.

Subjects fill out multiple questionnaires, and for half a year before filling
out the questionnaires, subjects will keep track of how often they had an
infectious disease (like flu or nasal cold). 30 ml of blood will be drawn from
sixty elderly subjects in the region. The study subjects will have no direct
benefit from the study.