Is dairy good for you? - PDF Free Download

Is dairy good for you? A focus on bone health Dr Johanita Kruger PhD Nutrition Department of Food Science and Institute of Food, Nutrition and Well-being, University of Pretoria

Radical consumer believes of harmful food Milk - Ultra-processed foods Sugar - Potatoes Red wine - Movie/microwave popcorn Soda - Fast foods Braaivleis - High/low fat Canned foods - High/low protein Sweetener - MSG Gluten - Carbohydrates

What is public opinion? What the public sees as bad for you Milk - Ultra-processed foods Sugar - Potatoes Red wine - Movie/microwave popcorn Soda - Fast foods Open flame meat - Canned foods Sweetener - MSG Gluten - High fat Low fat - High protein Low protein

What is public opinion? We re all going to What the public sees as bad for you Milk - Ultra-processed foods die we Sugar all - Potatoes eat food. Red wine - Movie/microwave popcorn Soda - Fast foods Therefore, food Open flame meat - Canned foods Sweetener - MSG must be the culprit. Gluten - High fat Low fat - High protein Low protein JIM WINDOLF

Various online and social media platforms wwww.solvecfs.org

www.nerdybaby.com

Changes in nutrition believes

Outline Important nutrients in milk Nutritional contribution of nutrients Nutritional significance of nutrients Association between milk and dairy consumption and bone health Other associations Dairy and weight management, Association with acne, constipation, gas and mucus production Prostate cancer, type 1 diabetes and multiple sclerosis

Nutrient content of milk and Macronutrients dairy products Carbohydrates lactose Fatty acids Saturated and monounsaturated Proteins Casein and whey protein Micronutrients Vitamins fat and water soluble Minerals trace and major elements

Vitamins Vitamin A (Vit A) Vitamin D (Vit D) Vitamin E (Vit E) Vitamin K (Vit K) Vitamin C (Vit C) Thiamine (Vit B1) Riboflavin (Vit B2) Niacin (Vit B3) Pantothenic acid (Vit B5) Pyridoxine (Vit B6) Folic Acid (Vit B9), Cobalamins (Vit B12)

Minerals Calcium (Ca) Phosphorus (P) Magnesium (Mg) Sodium (Na) Chloride (Cl) Potassium (K) Iron (Fe) Zinc (Zn) Copper (Cu) Selenium (Se) Manganese (Mn)

SA nutrient labeling Nutrient content claims Nutrient content per serving size Determine the contribution the nutrients can make towards the nutrient reference values (NRV) of individuals aged >4 years Nutrient content requirements for content claims Contribution to NRV Claim 0-<5% No 6-<15% No 15-<30% Source of 30 -<60% High in >60% Very high in South African Food Labelling Regulations (R146/2010); http://www.resp ond.za.net/

Percentage (%) contribution dairy can make towards nutrient requirements No t listed nutritional table Only listed in nutritional table Source of High in Very high in * Values are averages of whole, skim and fat free milk and yogurt Milk* Yogurt* Cheese Ca 23 15 16 Mg 6 4 2 P 18 17 12 Zn 10 8 10 Vit B1 9 5 1 Vit B2 34 34 9 Vit B6 5 6 1 Vit B12 51 43 17 Vit A 7 6 8

Contribution of dairy to nutrient intake 4 National Health and Nutrition Examination Survey (NHANES) between 2001 and 2008 n = 33 283

Contribution of dairy to energy intake - USA

Contribution of dairy to Ca intake - USA

Contribution of dairy to Vit D intake - USA

Contribution of dairy to Vit A intake - USA

Contribution of dairy to other nutrient intakes - USA Other nutrients: Age 2-19 K 22% Vit B 2 29% P 29% Vit B 12 29% Zn 16% Se 12% Other nutrients: Age >20 Vit B 2 29% Vit B 12 20% Zn 26% Se 8%

Contribution of dairy to nutrient intake National Individual Food Survey INCA2, 2005-2007 n = 3 362

Contribution of dairy to nutrient 50 40 45.6 intake of adults 30 20 29.8 28.2 24.7 19.6 16.5 14.5 14.3 10 0 Ca I Vit B2 P Zn Vit A Vit B12 Vit D First Contributor Second Contributor

Contribution of dairy to nutrient 60 50 53.2 intake of children 40 30 20 39.7 38.4 31 21.4 24.7 24.6 24.1 22.6 18.7 10 0 Ca I Vit B2 P K Zn Vit B5 Vit A Vit B12 Vit D First Contributor Second Contributor

Contribution of dairy to nutrient intake Dutch Food consumption Surveys (DFCS) 2003-2005 n = 8 451

Contribution of dairy to nutrient 80 70 60 50 40 30 20 10 0 24 17 73 66 58 41 39 29 intake 24 2119 16 18 16 11 12 12 7 8 3 Age 2-6 Age 19-65

Contribution of dairy to nutrient intake 70 73 66 60 58 50 40 30 20 10 0 24 17 2119 8 3 39 29 12 7 24 16 18 16 11 12 41 Age 2-6 Age 19-65 http://nolond.com/

Roles of nutrients in bone health Calcium Phosphorus Vitamin D Vitamin K Magnesium (http://www.duderanching.org/)

Alternative Ca food sources (http://www.agelessonline.net/)

Vitamin D sources Few food sources Skin can produce Vit D when exposed to the sun Risk factors for insufficient Vit D Pigmented skin Lack of sunlight exposure You need to spend half the amount of time in the sun that it takes for you to burn per day Skin concealing garments or strict sunscreen use

Recap Milk is nutrient dense Dairy can contribute substantial amounts of Ca, Vit B2, Vit B12, P and Zn to the diet Dietary recommendations affect dairy intake Vit D replaced by sun exposure Ca replacement difficult Reasonable expectation that dairy consumption would increase bone health?

Interpretation of studies Food factors Environmental and genetic variation Food processing and fortification Nutrient bioavailability Consumption variation Serving size Home food preparation Food combinations Consumer factors Age and sex Genetic (born) risk of disease Lifestyle factors

Interpretation of nutritional studies Type of study design Double blind randomised controlled studies Ethical and methodological concerns Prospective studies Cohort studies Follow a population with no fractures and then once fractures occur, go back and try and identify risk factors

How consumption of mozzarella cheese (US) relates to the amount of lawyers in Hawaii http://www.tylervigen.com/

How consumption of whole milk (US) relates consumption of corn syrup http://www.tylervigen.com/

Association between dairy intake and bone health Based in Sweden n=61 433 women and n=45 339 men

Conclusion of study High milk intake was associated with higher mortality in one cohort of women and in another cohort of men higher fracture incidence in women

Cautions of interpretation by authors Given the observational study designs with the inherent possibility of residual confounding and reverse causation phenomena, a cautious interpretation of the results is recommended.

Association between dairy intake and bone health n = 1402 men and women Sub-cohort smaller sample size, high level of historical information

Conclusion of study Higher total dairy, milk and yogurt intakes (not cheese and cream) are associated with higher BMD. No significant associations were observed for dairy intake and the risk of hip fracture except for milk and yogurt intake, which showed a marginally significant protective effect.

Cautions of interpretation by authors Consider the study group Age and ethnicity No clear indication of protective effect Lastly, more data are needed to better understand the association of dairy foods with hip fracture risk in men and women.

Association between dairy intake and bone health n = 41 000 men and women

Conclusion of study Higher calcium intake (1000 to 1300 mg/day) of which 42% of which was from dairy Associated with a decreased risk of incident fractures. Higher dietary calcium intake within the current recommendation is safe and likely to be beneficial to health

Cautions of interpretation by authors Limitations of study addressed No suggestions on interpretation More research needed

Association between dairy intake and bone health Systematic review and meta-analysis Reviewed 18 original research papers

Conclusion of study Only include conclusions on dairy Milk avoidance, high cheese intake and no breastfeeding associated with an increased fracture risk among children aged 2 13 years of age

Cautions of interpretation by authors From a public health perspective, the strength of the evidence available from this systematic review could only give a basis for preliminary nutritional conclusions. More high-quality longitudinal cohort studies are needed.

Association between dairy intake and bone health Systematic review 13 original research articles including their own.

Conclusion of study No relationship between milk or fermented milk consumption and mortality due to any cause. More research needed

Why the variation in results?

Conclusion of study No association between vitamin D intake and the risk of fractures in older Swedish women. More research needed

Recap More research needed Association of dairy with bone health In general both positive and negative Yogurt most consistent positive result Not consistent for milk and cheese Protective mechanism not necessarily increased BMD Most focus put on the contribution dairy makes to Ca intake Very little research done in Africa and/or on African populations

Take home messages Bone health is a complicated story Role of Calcium maybe overestimated? What about yogurt? IS DAIRY GOOD FOR YOU? There is no consistent research showing negative association between dairy consumption and bone health As with drinking water, all things should be enjoyed in moderation

Thank you very much! Department of Food Science and Institute of Food, Nutrition and Well-being, University of Pretoria