Reducing saturated fatty acids in the food chain through alteration of milk fat composition

The UK considerably exceeds its target for saturated fats in the diet, and milk and milk products are the single largest source contributing about 30-40% of the total with cheese and butter contributing most. There is however evidence that there are likely to be benefits in terms of reduced vascular disease and some cancers from increased milk consumption although the evidence for cheese, butter and cream is lacking. Thus simply reducing consumption of milk to reduce saturated fat consumption is likely to be counterproductive. Studies with humans where blood cholesterol has been measured suggest that replacing a proportion of the saturated fat in milk/milk products with mono or polyunsaturated fats does improve their health value. Also there is now good evidence that changing the diet of the dairy cows can lead to milk being produced with reduced saturates and increased monounsaturates although a consequence is often a small increase in trans fats. These trans fats are different to those produced by industrial processes and are not likely to be as harmful to health. Such changes to the diet of the dairy cow may also have another postive effect as they are likely to reduce the amount of methane (a potent greenhouse gas) produced by the cow thus reducing the carbon footprint of the milk. This project will examine the potential of approaches to reduce saturated fats in milk in on-farm production, in research aimed at reducing saturates further whilst minimising trans fat and methane production and will also study the health benefits of such foods in humans using new methods of assessing risk of cardiovascular disease. The project will be organised into four workpackages (WP): WP1 will study the changes in the various types of fat in milk when cows on a selection of commercial dairy farms are fed oilseeds in their diets scientifically proven to reduce saturates. Most work to date has been only in research centres and it is important to understand what happens in a commercial situation with many different factors (e.g. cow breed, background diet etc) WP2 will examine new approaches to the production of milk with reduced saturated fat and whilst minimising the amount of trans fat in the milk and methane produced by the cow. Trans fats are produced by bacteria in the digestive tract of the cow by changing the make up of fats in the cow's diet. Methods to 'protect' these fats from bacterial action will be studied. Bacteria in the digestive tract are also responsible for the methane produced. WP3 will undertake a detailed human study to assess the effect of including in the diet dairy products with reduced saturated fats and increased with mono or polyunsaturated fats. New, more valuable methods of assessing any change in the risk of cardiovascular disease will be included as these are thought to be more predictive than the more traditional approaches relying in blood cholesterol. WP4 will compile all the results and findings and will prepare a structured plan to disseminate the findings. The overall aim is to reduce the amount of saturated fat in the UK food chain. There is potential to reduce this by some 90,000 tonnes/year if the work led to widespread application. Also of note is the fact that the changes to the diet of the cow proposed are likely to have significant environmental benefits, mainly through a reduction in the amount of methane produced by the cow.

UK exceeds its dietary target for saturated fatty acids (SFA) and milk/milk products are the single largest source i.e. about 30-40% of total SFA. Recent data show that there are likely to be benefits in terms of reduced vascular disease increased milk consumption although the evidence for cheese, butter and cream is lacking. Simply reducing consumption of milk to reduce intake of SFA may be counterproductive. Using simple markers like as plasma cholesterol, there is intervention evidence that replacing a proportion of the SFA in milk/milk products does improve their health value to humans. Recent studies also show the potential of animal nutrition to enable dairy cows to produce milk with reduced SFA and increased cis-monounsaturated fatty acids (MUFA) although a consequence is often an small increase in trans fatty acids (TFA), mainly trans-11 18:1. The project will be comprised of four workpackages (WP) and will examine: WP1 will study the milk fatty acid response (SFA, MUFA, TFA and polyunsaturated fatty acids - PUFA in particular) when cows on a selection of commercial dairy farms are fed oilseed-based diets scientifically proven to reduce SFA. WP2 will examine new approaches to the production of milk with increased SFA/ MUFA/PUFA changes whilst minimising TFA in milk and methane produced by the cow. WP3 will undertake a detailed human intervention study to assess the effect of including reduced SFA/enhanced MUFA/PUFA dairy products in the diet on markers of cardiovascular disease/metabolic syndrome. There are very few studies investigating the impact of modified dairy products on cardio-metabolic risk and those published have only investigated lipid outcomes. However vascular reactivity and novel biomarker of vascular function (such as endothelial progenitor cell and microparticle number are novel, emerging, important additional CVD risk factors and will be studied. WP4 will integrate all data from the other WPs and prepare a dissemination plan.

Likely beneficiaries from the research: Commercial sector: The partner companies listed in this application Similar or related companies in animal feed supply, milk production, milk processing Companies involved in, dairy food retailing including the major supermarkets and companies who are users of milk products in other foods (e.g. cheese topping for pizza) Trade associations including National Farmers Union, International Dairy Federation, Global Dairy Platform Policy makers: UK: DEFRA, Food Standards Agency, Dept. of Health and similar bodies in devolved governments Government Advisory Committees (e.g. SACN, ACAF) EU: European Commission, EFSA and related bodies Public sector/charities: Levy bodies in Agriculture & Horticulture Development Board National Health Service Schools Approved providers of nutrition advice (e.g. British Nutrition Foundation) British Heart Foundation Public: Consumers will be able to obtain healthier foods reducing risks of ill health How will they benefit from this research? Impact on the nation's health, wealth or culture: This research is concerned with issues of great national relevance. The dairy industry produces foods with a total retail value of some £8.5 billion /year, sold mainly via retail outlets and habitually consumed by over 90% of the population of all age groups. Cardiovascular disease including stroke is still the largest cause of premature death and costs the UK some £18 billion per year, one of the highest per capita costs in the EU. The Food for Life report proposed that meeting nutritional guidelines would save some £20 billion per year. Impacts and their importance: A key long term impact would be on health and quality of life especially in an ageing population. Milk has a number of potential benefits to older people and an improved product would encourage increased consumption helping the maintenance of muscle mass and bone strength. The research has the potential to stimulate increased demand for dairy products in an increasingly health conscious society improving margins for dairy farmers. There may also be more export demand for dairy foods increasing the competitiveness of UK food industry. Timescales for the benefits to be realised: Marketing of improved dairy products would be possible within three to five years of project start with commercial benefits following. Health benefits would probably be seen over a longer period although there may be shorter term benefits from increased milk consumption. Research and professional skills: Staff working on the project will learn new knowledge related to parts of the food chain outside their normal area. It will for e.g. allow scientists a much better understanding of the commercial realities of food production and retailing as well as the social and economic facts relating diet to health. Ensuring benefit is derived This project is already highly engaged with partners in the food chain including companies/organisations concerned with dairy farm and milk policy, dairy cow dietary ingredients, milk buying and processing, laboratory analysis of a high proportion of UK milk and retailing of high value dairy foods. Such active engagement will ensure rapid transfer of outputs into practise and will thus lead to high impact. Outputs from the study will be disseminated via these and related stakeholders as well as by scientific papers, presentations at scientific conferences, and workshops. This is in addition to regular reports to BBSRC/DRINC and to the public via the media and appropriate consumer bodies. The senior scientists are well known internationally and are frequently invited to present papers to major conferences providing excellent opportunities for dissemination. They are also members of Government/related advisory committees to which presentations will be made. It is also planned to invite DEFRA and FSA to be keystakeholder members of the project management group.