With so many milk options available to consumers, how do you know which one is best for you and your clients? Linia Patel guides you through the various choices.
There is an increasing number of types of milk available to consumers. Which one should you be drinking? Is organic milk the same as grass-fed milk? How does cow’s milk differ from goat’s milk or almond or coconut milk? How about the new A2 milk? This article aims to answer these murky (or is it milky?) questions.
The most common variety of milk consumed is cow’s milk. Cow’s milk is available in a number of milk fat percentages: skim (fat free), 1%, 2% and whole (where no fat has been removed). As a general rule, nutrition experts recommend low-fat milk from two years onwards. Within my clinical practice (depending on nutritional goals), if you are consuming less than one pint of milk a day, I am increasingly open to the amount of fat you choose to have in your milk. For me, the quality of the milk you consume is key.
The milk you drink will only be as healthy as the cow that produced it. Surveys suggest that people associate organic milk with superior nutrition. Organic farmers must use organic fertilisers and pesticides and must not give cows preventative antibiotics or supplemental growth hormones. Studies have shown that organic milk contains at least 60% more omega-3 fatty acids than non-organic milk.1 However, your choice should not stop at organic. Grass feeding is a practice not yet familiar to all consumers. 100% grass-fed cow’s milk comes from cows that have grazed in pasture (or eaten dry forage) all year round rather than being fed a processed diet of grains like corn and soya. Organic cows are not required to be solely grass fed; however, they must have at least 120 days per year of grazing. For the rest of the time, organic cows can be fed grains. The natural diet for ruminant animals such as cattle is plain grass. Hard-to-digest grains radically alter the bacterial balance and composition in the animal’s gut. Just as for humans, poor gut health in animals promotes disease and also radically alters the nutritional composition of the milk2.
A recent study from Couvreur et al showed that grass-fed cows produced milk with 15% more healthy, hearty omega-3 fats and 32% more conjugated linoleic acid (CLA). CLA is a type of fatty acid that is found naturally in milk primarily from ruminants such as cows. CLA exhibits potent antioxidant activity and some research indicates that CLA might be protective against heart disease, diabetes and cancer2.
A study from Elgersma et al also showed that grass-fed cows produce milk that is richer in micronutrients and phytochemicals. In the study, grass-fed cow’s milk had 22.9% more B12 and 18.7% more iodine than grain-fed cow’s milk, for example. The milk was also significantly richer in beta-carotene. Carotenoids such as beta-carotene are precursors to vitamin A that are found as pigments in plants. Cows that eat carotenoid-rich grass and forage, therefore, are able to incorporate significant amounts of these compounds in their tissue and, therefore, their milk1.
Milk contains many proteins, one of which is called beta-casein. A1 and A2 are two common forms of beta-casein. Recent nutrition surveys show that 20% of the UK population struggles to digest milk protein. Milk labelled as ‘A2 milk’ contains mainly the A2 type of beta-casein. The milk currently available in supermarkets and known as ‘conventional milk’ contains a mixture of A2 and A1 beta-casein (about 60% A2 and 40% A1). There is an emerging body of evidence implicating A1 beta-casein in a range of human health conditions, many of which have an auto-immune element to them (i.e., type I diabetes, heart disease, mental health conditions, child development)3,4,5. If you have diagnosed milk protein intolerance or have a family history of auto-immune diseases, you may want to consider A2 milk. However, one drawback is that the A2 on the market is not organic or 100% grass fed.
Goat’s milk is more easily digested by some as it contains smaller proteins and fat globules to those found in cow’s milk. It contains as much protein and calcium as cow’s milk and contains more tryptophan (an essential amino acid) than cow’s milk. However, goat’s milk still contains lactose, which will eliminate it as a choice for some6. It also has a very distinct taste, which some may dislike.
Like goat’s milk, sheep’s milk has smaller proteins, smaller fat globules and more medium-chain triglycerides (MCTs) which aid digestion. As sheep feed 100% on grass, sheep’s milk has more CLA than the milk from cows or goats. Sheep’s milk also contains up to twice as much calcium and B vitamins as cow’s or goat’s milk. However, it contains as much lactose as cow’s milk, so isn’t a great alternative if you’re lactose intolerant. One drawback of sheep’s milk is the cost. Sheep produce much less milk than cows and goats, hence sheep’s milk is likely to be more expensive7. All milk that comes from an animal will contain some lactose sugar, hence, if you are lactose intolerant, you may want to consider using a milk substitute from non-animal sources. These include almond, rice or coconut milk, for example. As the nutritional composition of these milk substitutes lacks many of the key micronutrients contained in animal milk, like calcium or vitamin D, these milk substitutes are often fortified with nutrients to make them more marketable7.
Almond milk is a popular vegetarian alternative for those allergic to dairy or soy. Almond milk also has a naturally sweet taste. In terms of calcium content, it is comparable to cow’s milk. On the downside, despite containing only 60 calories per cup, almond milk is not a great protein source (1g per cup vs 9g per cup in cow’s milk). It is also high in sugars. It is also not suitable for those with nut allergies and lacks the B vitamins in cow’s milk. If you do choose almond milk, go for one that is unsweetened and fortified with vitamin D8,9.
Coconut milk is another alternative to cow’s milk. It is lactose free and suitable for vegetarians and vegans. Coconuts are high in saturated fats but the fats come from MCTs. MCTs are fats with an unusual chemical structure that allows the body to digest them easily. These fats can be used immediately as an energy source. Coconut milk also contains a high level of potassium. The drawbacks to coconut milk are the low protein and calcium content and the high calorie count. One cup of coconut milk is approximately 450 calories, whereas a cup of whole milk is approximately 147kcal7,8. If you do choose coconut milk, it is important that you consider coconut milk as a fat source rather than a protein source – and remember portion control!
Rice milk is another vegetarian/vegan option that is also lactose free. It is made from ground rice and hence is naturally lower in protein and calcium in comparison to regular milk and higher in carbohydrates than cow’s milk. It is not recommended for children due to its low protein and calcium content8,9. If you are choosing rice milk, choose a variety that has been fortified with calcium and protein.
About the author
Linia Patel has a BSc degree in biochemistry and physiology. Since graduating in 2006, Linia has taken up various leading roles in performance nutrition and public health. liniapatel.com
- Elgersma A, Ellen D, Van der Horst H et al (2004), Quick changes to milk fat composition from cows alter transition from fresh grass to a silage diet, Animal Feed Science and Technology, 117: 1-2.
- Couvreur S, Hurtaud C, Lopez C et al (2006), The linear relationship between the proportion of fresh grass in the cow diet, milk fatty acid composition and butter properties, Journal of Diary Science, 89.
- Laugesen M, Elliott R (2003), Ischaemic heart disease, Type 1 diabetes, and cow milk A1 beta-casein, N Z Med J, 116(1,168): U295.
- Haq MR, Kapila R, Sharma R, Saliganta V, Kapila S (2013), Comparative evaluation of cow Î²-casein variants (A1/A2) consumption on Th2-mediated inflammatory response in mouse gut, European Journal of Nutrition, Epub 2013/10/10.
- McLachlan CN (2001), Beta-casein A1, ischaemic heart disease mortality and other illnesses, Med Hypotheses, 56(2): 262-72.
- Mehaia M, Mohamed A, Studies on goat milk proteins: Nitrogen distributions and amino acid composition, Nutrition Reports International, 39(2): 351-357.
- Milk Facts, http://milkfacts.info/Nutrition%20Facts/Nutrient%20Content.htm, accessed 11 November 2014.
- The Diary Council, http://www.milk.co.uk, accessed 11 November 2014.
- Alpro Milk, http://www.alpro.com/uk, accessed 11 November 2014.