Recently, there have been several controversies around the selection of dairy foods. I decided to unearth the facts to make sound nutrition recommendation for future dietetic practice.
Does the selection of dairy with reduced fat content, e.g. low-fat milk, fat reduced cheese or fat-free yoghurts contain added sugar to maintain the palatability of these foods? The answer varies. I went to Woolworths to compare between several dairy foods (based on per 100 g) and realise not all low-fat dairy will have higher sugar content. Furthermore, it is difficult to determine whether the sugar is added sugar or natural milk sugar, lactose.
Milk
There is a limited variety of powdered milk options available. Devondale full-cream fresh milk powder and skimmed milk powder (the only two varieties available; other brand available: Woolworths Select), the skimmed alternative (contain 0.1% fat).
Devondale Full-Cream Fresh Milk Powder contain 303 kJ, 4 g fat (2.7 g saturated), 5.6 g sugar, 47 mg sodium, 117 mg calcium.
Devondale Skimmed Milk Powder contain 157 kJ, 0.1 g fat (0.07 g saturated), 5.3 g sugar, 45 mg sodium, 115 mg calcium.
Skimmed milk powder contains slightly less sugar (but type of sugar unknown), and with nutrient density decreased with lower fat content.
Pauls Zymil Full Cream Milk contain 270 kJ, 3.6 g fat (2.3 g saturated), 4.7 g sugar (NIL lactose because it is lactose-free, 2.4 g galactose), 40 mg sodium, 125 mg calcium.
Pauls Zymil Low Fat Milk contain 189 kJ, 1.3 g fat (0.8 g saturated), 4.9 g sugar (NIL lactose because it is lactose-free, 2.4 g galactose), 40 mg sodium, 122 mg calcium.
The same observation was seen with milk powder besides a slightly increased sugar content. If it is not accounted by lactose and galactose, it could be added sugar.
A full-cream milk powder can prepare approximately 7 L of milk while a skimmed milk powder can prepare up to 10 L. Comparing the price of powdered milk, $8.99 (not on offer) to pasteurized or fresh milk, it is relatively cheaper to buy powdered options.
Cheese (per 100 g)
Kraft Cheddar Sandwich Slices contain 1394 kJ, 27.4 g fat (18 g saturated), 2.2 g sugar, 1736 mg sodium, 581 mg calcium.
Kraft Singles Original contain 1160 kJ, 20.9 g fat (14.8 g saturated), 2.4 g sugar, 1350 mg sodium, 1190 mg calcium.
Kraft Singles Light (25% less fat) contain 911 kJ, 15.4 g fat (10.9 g saturated), <1.0 g sugar, 1380 mg sodium, 1010 mg calcium.
Homebrand Processed Cheese Slices contain 1210 kJ, 23.7 g fat (16.5 g saturated), <1.0 g sugar, 1500 mg sodium, 470 mg calcium.
Homebrand Processed Light Cheese contain 1030 kJ, 15.7 g fat (10.7 g saturated), <1.0 g sugar, 1170 mg sodium 643 mg calcium.
Based on the above nutrition information from the nutrition label, it seems that with lower fat content, cheese contains less sugar and sodium, but calcium content increased. Another comparison you can see is that the type of cheese has great influences on the fat, sodium and calcium content.
Yoghurt
Tasmanian Tamar Valley Dairy No Fat Natural Yoghurt contain 231 kJ, <0.15 g fat (<0.1 g saturated), 6.7 g sugar, 71 mg sodium 199 mg calcium.
Tasmanian Tamar Valley Dairy Greek Style All Natural Yoghurt contain 542 kJ, 9.8 g fat (5.9 g saturated), 5.2 g sugar, 58 mg sodium 160 mg calcium.
But it is also important to note the choice of yoghurt. If flavoured yoghurt is chosen, added sugar content is likely to be higher. The varieties of yoghurt, e.g. Greek style may influence the nutritional content too.
If selecting dairy foods for a healthy diet, choosing a fat reduced option is the right choice to make. Dairy foods (an animal produce) contain fat mostly as saturated fat that may increase low-density lipoprotein cholesterol (LDL-C) and total cholesterol, increasing the risk for cardiovascular disease (CVD). Thus, choosing low-fat dairy reduces the intake of saturated fat, protecting against complications associated with heart health. It benefits patients with type 2 diabetes where a major macrovascular complication is CVD. Furthermore, consumption of 200 g dairy foods/d can decrease the risk of T2DM by 4%; 80 - 125 g/d yoghurt can decrease the risk of T2DM by 14%. Further research is required to determine whether plain or sweetened yoghurt varieties influence the risk of developing T2DM.(1)
If a person is making his/her selection with weight loss as a priority, it is important to continue getting enough dairy serves in the diet. A weight loss diet often creates an energy deficit, and that omits some foods (including those that may be nutritious) from the diet. However, the complete elimination of dairy foods with concerns over its fat content is not necessary and should not be advocated. Dairy foods contain fat and protein accompanied with calcium important for building strong bones to protect against deficiency disease, e.g. osteoporosis. Fat and protein also provide satiety, keeping a person full for a longer period of time, thus less likely to overeat. Finally, energy balance influences a person's weight. To achieve a safe, gradual weight loss of 0.5 - 1 kg/week requires creating a deficit of 2000 - 4000 kJ/d. That being said, it is the overall calorie intake and not the fat intake that matters.
What if a person is lactose intolerant?
A person may be recommended to drink up to 250 mL of milk with small amounts spread across the day. Most hard cheeses, e.g. cheddar are lactose-free Yoghurts contain probiotics which can help with lactose digestion. Besides dairy, there are alternatives, e.g. tofu, legumes, nuts (esp. almond) where they can obtain their calcium needs.
(1) Gijsbers L, Ding E, Malik V, de Goede J, Geleijnse J, Soedamah-Muthu S. Consumption of dairy foods and diabetes incidence: a dose-response meta-analysis of observational studies. Am J Clin Nutr. 2016;103(4):1111-1124.
