Why yogurt is good for you
By Aveen Bannon RD
Here at Glenisk we’re firm advocates for the benefits of yogurt at all life stages – from supporting growing babies and kids to helping to maintain strong bones in our later years…but don’t just take our word for it! Consultant Dietician, Aveen Bannon also shares her expert opinion on the health benefits of yogurt.
Yogurt is considered a nutritional powerhouse that when taken regularly can promote health at every life stage. Predominantly known as a calcium rich food, it also may enhance healthy gut bacteria and provides protein, calcium, magnesium, vitamin B12, CLA (conjugated linoleum acid) and iodine, a mineral essential for thyroid. What makes yogurt unique in its nutritional benefits is something we describe as the food matrix – this basically means that the combination of the nutrient profile provides added health benefits by enhancing nutrient absorption and digestion. When we look at foods we need to look at the whole nutrient profile. Foods are more than just vehicles that deliver particular nutrients to the body – they are a package of nutrients which interact or act together to influence our body and health….Yogurt is a perfect example of this.
Research from several countries including Ireland and the UK shows that children and teens’ diets are not sufficient in calcium. Calcium is an essential mineral for bone health and the recommended intake (RDA) is 800 mg/day for children, adults and older people which equates to 3 servings per day. The RDA increases to 1200 mg for teenagers, pregnant and lactating women, which equates to 5 servings per day1. Unfortunately, 16% of women in Ireland are not consuming enough calcium2. The National Children’s Food Survey also found that 28% boys and 37% girls aged 5-12 years have inadequate calcium intakes3.
The richest food sources of calcium in the diet include milk, cheese and yogurt. Green vegetables, bread and tinned fish also provide some calcium. However, the bioavailability of calcium from non-dairy sources is lower, this is related to the food matrix effect that I described above. Research has shown that calcium when ingested with protein, casein phosphatides, lactose, magnesium and phosphorous increases calcium absorption. These compounds are all components of dairy. Furthermore, fermented milks i.e. yogurts are thought to enhance calcium absorption further4.
More recently regular consumption of yogurt has been associated with helping weight loss and maintaining a healthy body weight. The reason for this is possibly twofold…one is that it is a naturally a high protein low calorie food, the second is regular consumption of healthful foods such as yogurt results in decreased intake of less healthful foods containing higher amounts of fat and/or sugar. When we look closer at both milk and yogurt we note that milk proteins, whey and casein, differ in terms of absorption rate and post-absorptive responses…this in turn influences their satiety properties. Studies have shown that consumption of milk and yogurt increases the circulating concentration of the anorectic peptides glucagon-like peptide (GLP)-1 and peptide YY (PYY)5. This protein effect coupled with the food matrix can influence both appetite and satiety therefore help weight management.
Another factor of note is the fermentation process of yogurt. Yogurt is a fermented milk that contains bacteria which enrich the microbiota of the host. The lactobacillus and streptococcus strains have shown healthy benefits for those suffering with altered digestive patterns like constipation or diarrhoea, allergies and inflammatory bowel disease6. We also now know that gut microbiota differs between lean and obese individuals. Fermented foods have been shown to help improve the gut microbiota profile which in turn can help promote weight loss and help maintain a healthy weight.
In addition to weight benefits more recently evidence has shown that those who consume yogurt regularly have a lower risk of cardiovascular disease4. Research showed that consuming yogurt more than once per week was associated with improved insulin profiles which help manage weight and reduce heart disease risk7. A review of 18 observational studies found that yogurt consumption can decrease your likelihood of experiencing heart disease later in life8. One particular study showed that participants who had more than two servings of yogurt per week had a 20% reduced risk of suffering from congenital heart disease or strokes in future. Furthermore, the women who had two or more servings of yogurt a week were found to be 30% less likely to experience a heart attack. Similarly, men who consumed more than two servings of yogurt a week had a 19% reduced risk of heart attack9.
Iodine is often a forgotten mineral that the body needs to make thyroid hormones. These hormones control the body's metabolism and many other important functions. The body also needs thyroid hormones for proper bone and brain development during pregnancy and infancy. Milk, yogurt and other dairy products are the principal source of iodine in the UK & Irish diet. Other rich sources include seafood, seaweed and eggs10. Anyone who completely avoids dairy products and fish or consumes them in limited quantities is at risk of iodine deficiency. Unfortunately, at present many dairy-milk substitutes are not enriched with iodine. More recently there has been evidence that shows women of childbearing age are iodine deficient which is of concern. It is advised that women should ensure that they are meeting iodine requirements prior to conception to ensure good thyroid stores.
All of the above research is of course related to natural yogurts that have no added or very little added sugar. Sugar is a very topical issue at the moment with current advice from the WHO stating that we should be aiming for <10% of total daily energy intake to come from sugar11. With these recommendations the WHO very clearly state they do not include fructose naturally present in whole fruit or the lactose naturally present in milk and yogurt. A yogurt with no added sugar or small amount of sugar will still offer all the health benefits mentioned above.
- Food Safety Authority of Ireland (FSAI) (1999) Recommended Dietary Allowances for Ireland, Dublin: FSAI.
- Irish University Nutrition Alliance (IUNA) (2011) National Adult Nutrition Survey, Dublin: IUNA.
- Irish University Nutrition Alliance (IUNA) (2005) National Children’s Food Survey, Dublin: IUNA.
- ‘Whole dairy matrix or single nutrients in assessment of health effects: current evidence and knowledge gaps’, Am J Clin Nutr. 2017 May;105(5):1033-1045.
- ‘Impact of yogurt on appetite control, energy balance, and body composition’,Nutr. Rev 2015 August; Vol 73, Issue suppl_1, 23–27
- ‘Yogurt and gut function’, AJCN 2004, Vol 8 Issue 2
- ‘Is consuming yoghurt associated with weight management outcomes? Results from a systematic review’,Int J Obesity 2016; Vol 40:731-746
- ‘Dairy and Cardiovascular Disease: A Review of Recent Observational Research’,Curr Nutr Rep 2014; 3(2):130-138
- ‘Regular Yogurt Intake and Risk of Cardiovascular Disease Among Hypertensive Adults’, Am J Hypertension 2018 April; Vol 31, Issue 5:557–565
- Iodine deficiency in the UK – dietetic implications. British Dietetic Association
- Sugars intake for adults and children Guideline, WHO