Paediatric and Teenage Nutrition

food, feeding and nutrition

Tag: cow’s milk allergy

what’s the difference between lactose intolerance and cow’s milk allergy?

Many people are confused about the difference between lactose intolerance and cow’s milk allergy. Misunderstood as same condition; the terms lactose intolerance and cow’s milk allergy are used interchangeably and incorrectly.  Most likely due to the similarity of symptoms such as bloating, wind and diarrhoea;  both being related to drinking milk and alleviated by avoiding it. When I say milk – I mean mammalian milks such as cow’s (including infant formula) goats, sheep and human milk.  So, here is the main difference:  Cow’s Milk Allergy is an immune system response to milk protein, which drives a spectrum of symptoms affecting the skin as well as the tummy.  In the more severe IgE allergic reactions, the mouth, throat and breathing are affected. Lactose intolerance is not an allergy but a physical response due to lack of digestive enzyme lactase required to digest the milk sugar lactose. This blog will give an overview of symptoms, causes and dietary management of lactose intolerance providing further links on products and nutritional information.

Lactose Intolerance
Is a normal response to the presence of undigested lactose (milk sugar) in the large intestine. When lactose digestion fails in the small intestine the lactose sugar travels onto the large intestine where bacterial fermentation, responsible for the characteristic bloating, discomfort and wind, takes place. In the presence of large amounts of lactose, water and salts are drawn into the large bowel (by osmosis) causing increased water volume, urgency to go to the toilet and explosive stools. Lactose is found in milk and dairy products like soft cheese and yoghurts.  Hard cheeses have naturally low levels of lactose, as do products like butter, margarine and double cream.  Adults and older children with established lactose intolerance can typically eat these foods without any problem. Those small amounts of lactose provide food for the friendly lactobacillus bacteria which normal live in the large bowel.

What are the causes of lactose intolerance?
Lactose intolerance itself does not cause damage to the small intestine; rather it’s the result of tissue damage to the intestinal lining which affects lactase enzyme production.  A temporary condition in infants and young children, it will resolve as the gut cells turnover and repair themselves. Lactase enzyme decreases progressively with age with around 70% of the world’s population with limited lactase activity.  Persistent lactose intolerance is uncommon in infants and young children, due to their high milk intake, which maintains enzyme production. Teenagers however may not regain their lactase activity following small intestinal damage or serious infection.  The most common causes of lactose intolerance include:

  • Gastro-intestinal infection with characteristic diarrhoea and vomiting
  • Allergic inflammation, especially with unresolved non-IgE Cow’s Milk Allergy
  • Small bowel bacterial overgrowth eg. in older children, teens

Products and differences in dietary management 
It’s important to understand that the nutritional composition of milk alternatives make them unsuitable as drinks for infants and toddlers, but can be a useful addition to solids, when a nutritious fluid is needed to blend or mix.  When selecting a milk alternative, always choose one fortified with calcium. Lactose free milks and cheeses made from cow’s milk contain cow’s milk protein, making them unsuitable for those with cow’s milk allergy.  Vegan cheeses, whilst lactose and cow’s milk protein free have poor nutritional value and are not fortified with any calcium.  A low lactose diet to treat lactose intolerance is usually followed for between 2 and 6 weeks (depending on severity of symptoms) and a cow’s milk protein exclusion for CMA for at least 6 months. Use this guidance on reintroducing lactose back into the diet  if you had lactose intolerance but do seek further guidance for Cow’s Milk Allergy in Infancy if feeding is difficult and you are unsure about next steps.

reintroducing lactose back into the diet

Following a 2 – 6 week low lactose diet to treat lactose intolerance, your child should now be well on their way to recovery from symptoms.  Reintroducing lactose back into the diet in a controlled way is the next step. Starting with low lactose foods, then adding in medium and, once you’re satisfied all is being tolerated, finally adding in high lactose-containing foods. Use the guidance below on lactose content of dairy foods to assist you, taking about 2-4 weeks, gradually increasing, will do several things:

  • stimulate production of lactase, the small intestinal digestive enzyme that digests lactose
  • help establish and then increase the amount of dietary lactose that is tolerated
  • assist in the build up and return of normal lactase production in the small intestine

Re-establishing tolerance to lactose
Re-establishing tolerance to lactose varies from child-to-child, depending on age, habitual diet and degree of severity. Because infants and young children are more dependent on a high milk diet, the lactase enzyme returns more readily and lactose intolerance is usually temporary.  Resumption of a normal diet is somewhere between 2-6 weeks for most infants and children. Referred to as secondary lactose intolerance this is often the result of nasty gut bugs like rotavirus, or can be secondary to small intestinal damage caused by untreated cow’s milk protein allergy or coeliac disease. Individuals including older children and teens may develop primary lactose intolerance or a permanent reduction in lactase enzyme, more typically affecting non-caucasian children and those with a habitually low milk/no milk intake following a similar route via infection of small intestinal irritation.  Amounts of 2 – 4g lactose per day are usually well tolerated despite the lack of lactase enzyme.  Instead lactose is digested by the lactobacillus bacteria, naturally residing in the large intestine.

Other points worth noting about lactose intolerance and reintroduction

Special care with infants
Formula fed babies with lactose intolerance, need a lactose free formula. Lactose intolerance may also occur in breast-fed babies but is less common; only in very rare congenital primary lactase deficiency would there be a need to stop breast feeding and use a lactose free formula. What is important, is to correctly identify if cow’s milk allergy are the cause of the symptoms, to ensure that infants get the right dietary treatment. Products in the shops vary enormously in nutritional composition, and are not suitable to drink because of poor nutritional quality.

Lactose content of dairy foods

Very Low Lactose

< 2g per portion

Medium Lactose

2-4g per portion

High Lactose

4-6g per portion

The foods in this group contain very low amounts of lactose and are tolerated by most people with lactose intolerance.  If consuming these foods does not give any symptoms, try medium lactose foods per portion. Continue to introduce lactose containing foods, including foods with medium lactose. If symptoms return, go back to the previous tolerated stage for 2 weeks and try again. In addition to very low and medium lactose content foods, continue to introduce lactose-containing foods, including one portion from the high lactose category.
Cheese 1oz
Most hard cheeses have very small amounts of lactose and are unusually well tolerated. Eg. cheddar, red leicester, caerphilly, stilton, parmasan Cheese spread, cottage cheese, soft cheeses eg. ricotta, marscapone, dolchelate Cheese spread, quark


Yoghurts & fromage-frais 60g 125g Larger portion
Greek yoghurt, Goat’s yogurt, all yoghurts and fromage-frais Yoghurts and fromage-frais, Low fat fruit yoghurts, Organic whole milk yoghurt Natural whole or fruit yoghurt, Low fat natural yoghurt, Diet/low calorie yoghurts
Dairy desserts & creams 2oz 4 – 6oz Larger portion
Half fat cream, Single, Double, Whipping, Clotted cream, UHT Spray Cream, Fresh Cheese Cake 1 scoop ice cream, Frozen cheesecake, Trifle with cream, 1 chocolate mousse 2 scoops ice cream, 10mls Angel Delight, 150g tinned rice pudding, 100mls Custard
Hidden milk
1 x small slice cake, 4 chocolate digestives, 1 chocolate coated biscuit eg. 2 finger kit-kat, 100g egg custard tart 1 milk chocolate bar, 125mls whole milk, 70mls evaporated milk, 1 tblsp skimmed milk powder, 40mls condensed milk

risk of iodine deficiency during pregnancy

The nutrient iodine has been under scrutiny over recent years, due to public health concern that 50% of UK women are at risk of iodine deficiency.  Health consequences include thyroid dysfunction, goitre and poor mental function. Pregnant women are particularly at risk of iodine deficiency, and their unborn babies at increased risk of brain damage. The purpose of this blog is to highlight iodine deficiency as a real problem for pregnant women, provide guidance on dietary sources of iodine, suitable iodine supplementation and links to expert information via The UK Iodine Group.

Why is iodine deficiency so important?
Iodine is a constituent of thyroid hormones, essential for thyroid function and optimum functioning of the nervous system.  Importantly, during early pregnancy iodine is essential for the healthy brain development of the foetus, and later in pregnancy provides iodine directly to the baby for maturation of the thyroid gland. Iodine deficiency during pregnancy is linked to brain damage; the more profound the deficiency, the more severe the health consequences for the developing foetus.  This is a world-wide longstanding problem, and you can see a UK perspective the SACN statement on Iodine and Health published in 2014.

Dietary sources of iodine
Iodine comes from the soil, leaches into water and is naturally found in fish, shellfish and other seafood.  Iodisation of salt was not adopted in the UK, as it was across the US, China, Asia and Europe throughout the 1920’s.  In the UK it enters our food chain via dairy farming practice, as a constituent of sterilisers used in milking and of winter cattle feed. Together with encouraging children to drink more milk after WW2, cow’s milk is now the  main dietary source of iodine in the UK.  However our dietary practices are changing – we drink less cow’s milk, eat less fish and consume a more plant-based diet.  As a result we are  becoming iodine deficient.  There are calls for iodisation, but as we have no consensus. Do have look at other dietary sources of iodine to check on your own intake.

Increased needs for iodine during pregnancy and breastfeeding

  • Needs for iodine are 40% higher during pregnancy and breast-feeding
  • There is a 50% surge of thyroid hormone production during the early part of pregnancy, mainly to supply iodine to the developing foetus. Mum’s daily needs for iodine are 200-250ug
  • There are increased urinary losses during pregnancy
  • Iodine is required by the unborn baby from around 20 weeks gestation, to support the start of thyroid function; drawing this from maternal iodine supplies
  • Once born babies daily needs for iodine throughout the first year are 50-60ug and breast milk contains around 7ug/100mls (formula contains 12-14ug/100mls)

Taking an iodine supplement
Breast feeding mums are at further risk of iodine deficiency if following a milk free diet for their cow’s milk allergy baby. It is important to be aware that the nutritional composition of milk alternatives is poor, usually without iodine and sometimes even without calcium!  Do take a supplement if you cannot get enough iodine from dietary sources, bearing in mind that single supplements of iodine are not routinely available (partly because too much is dangerous). Pregnant women should not take kelp or seaweed supplements for this reason. Multivitamin & mineral supplements now routinely contain iodine, providing around 150ug, which is the usual daily adult need. The rest can more easily be found in the diet.

good sources of calcium

Infants and children need good sources of calcium in their diets on a daily basis. Calcium absorption in the gut is variable and ranges from 25-50%, increasing when intake is low and reducing when intake is high. Plenty of foods rich in calcium are especially important throughout infancy to support the rapid bone growth and bone mineralisation that occurs at this time. The uptake of calcium by bones is then regulated by Vitamin D, with Vitamin D deficiency limiting bone mineralisation even in the presence of adequate calcium.  Growth spurts during infancy and childhood, from a surge in growth hormone provides a boost to calcium absorption, which further strengthens bone mineralisation. Absorption of calcium from breast milk is very efficient at around 66% and from formula milk around 40%.   For all infants and young children offer them calcium rich foods every day.

  • Dairy products like milk, cheese and yoghurt are the UK’s best sources of calcium for infants and young children
  • Calcium is also found in tinned fish, nut butters, tahini or sesame seed pulp, hummus, figs, dates, and green vegetables
  • White wheat flour is fortified in the UK with 120mg Calcium per 100g
  • Water in areas of hard water like Cambridge contains 120mg calcium per litre
  • For all children with cow’s milk allergy, take care to offer calcium enriched products, checking sources of other valuable nutrients such as protein, iodine, Vitamin D as well as overall calories
  • Prolonged poor calcium intake will lead to brittle bones that break more easily, both in childhood and in later adulthood
  • Exercise and weight bearing activity will also strengthen bone
  • Have a quick check on recommended intakes to check if your child is getting enough calcium
  • Download the portions of calcium rich foods below
  • Infants and young children need a Vitamin D supplement containing a minimum of 10ug daily until 5 years and thereafter for a minimum of the 6 Winter/Spring months to maintain good levels

Recommended Intakes

  • Daily calcium needs during infancy are 525mg 
  • 5-600mls formula provides the majority of calcium during infancy
  • Breast fed infants depend on mum’s diet, and a calcium and vitamin D is advisable for mum
  • Daily calcium needs during early years are 350-450mg; provided by 3-4 portions of calcium rich foods
  • Daily calcium needs during primary school are 450-700mg; provided by 4-5 portions of calcium rich foods
  • For all children with cow’s milk allergy, take care to offer calcium enriched products, checking sources of other valuable nutrients such as protein, iodine, Vitamin D as well as overall calories.


nutritional composition of milk alternatives

If you have a child who has lactose intolerance or cow’s milk allergy, chances are you need to think about the nutritional composition of milk alternatives. Cow’s milk and its products are good sources of calcium and trace elements like iodine in the UK diet.  As someone who takes nutrition seriously, a Paediatric Dietitian and mother of 3 growing teenagers, I would like to point out that the nutritional composition of milk alternatives available in our shops is shockingly poor.  It does not serve consumers well, has insufficient nutrition for infants, children or teens, and for those who depend on the nutrients milk would normally provide.  The missing nutrients and their physiological roles are as follows:

  • calcium – for growth and maintenance of strong bones, blood clotting
  • iodine – for neurological development during pregnancy, control of metabolism, thyroid function
  • Vitamin B2 – for healthy skin, eyes and nervous system, releasing energy from food
  • protein – for growth and repair of all body tissues, immune function
  • Vitamin B12 – assists in maturing red blood cells, absorption of iron
  • lactose – the milk sugar – food for the beneficial lactobacillus genus of bacteria, maintenance of a healthy intestinal microbiota

Exciting range of nut milks
I was quite excited to see such an explosion of nut milks now routinely available; and on researching this recently, felt somewhat aggrieved to see such poor nutritional composition.  Nuts are one of nature’s most incredibly nutritious foods – high in calories, protein, essential fats, minerals like zinc, calcium, iron and magnesium as well as B vitamins. They are also (currently) fairly conflict-free and sustainable. There are not many foods you can say that about! Unfortunately none – and yes I do actually mean NONE – of that goodness is retained in the resultant, washed out and expensive product marketed as milk.  Some have no calcium, no protein, no minerals no vitamins, and poor calories. Mil for mil they are 7 times the price.

Compare the nutritional composition of milk alternatives in the chart below, and take care to ensure that you choose ones with higher calories and protein for young children, ensuring they are fortified with calcium, and where possible Vitamin D and other vitamins.

Type of Milk Calories Protein Calcium Vitamin D Extras
Whole Cow’s Milk 69 3.3 120 Low Wide range of nutrients
Cow’s Milk formula 66 1.3 65 1.2 Full range of nutrients
Mature Breast Milk 67 1.3 35* Varies Wide range of nutrients
Goats Milk 70 2.8 120 Low Wide range of nutrients
Arla Lactose Free Milk 56 3.3 120 Low Wide range of nutrients
KoKo unsweetened 16 0.2 120 0.75 Nothing
Oatly Original 46 1.0 120 1.5 Vitamins
Innocent Hazelnut Milk 72 1.0 0 0 Nothing
Innocent Almond Milk 37 1.4 0 0 Nothing
Alpro Soya Original 42 3.3 120 0.75 Vitamins
Alpro Cashew Milk 23 0.5 120 0.75 Vitamins
Alpro Soya Growing-Up 1-3 64 2.5 120 1.5 Iodine, Vitamins
Rice Dream plus calcium 50 0.1 120 0.75 Not for <5years
  • absorption of calcium from breast milk is extremely efficient, but infants needs for calcium from 6-12 months through are high.  Check out  good sources of calcium if weaning your cow’s milk allergic infant.

diet related conditions in childhood

Diet related conditions in childhood benefit from the skilled help of a Paediatric Dietitian, especially when foods are affecting a child’s eating, sleeping, playing or growing.  Do browse this section or get in touch with a question or to make an appointment.  Does you child have adverse reactions to foods or a diet-related medical condition?  Perhaps you have concerns that your child is not eating or growing well enough?  Are you concerned that your child has lost weight recently? Whatever their age, a child’s diet makes a huge contribution to their wellbeing. This website, and the service I offer, help to provide you with an understanding about, and treatment for, some common diet related conditions in childhood. To use the Paediatric Nutrition website, navigate age-related issues using the top bar and condition-specific ones using tabs on the side bar. A quick overview then:

The Infant feeding matters section contains information about diet related conditions in infancy such as cow’s milk allergy, and also gives an overview of an infant’s nutritional needs.

Food refusalCommon feeding difficulties in childhood that affect toddlers and pre-school children include behavioural issues such as food refusal and functional problems like constipation.  As needed, I work with other colleagues including paediatricians and speech and language therapists at Cambridge Paediatric Practice.

Food allergies and intolerance can affect all age groups, although food allergies do more commonly affect younger children.  Most early food allergies are outgrown by puberty, but those that persist or are diagnosed later in childhood are often life-long, requiring an epipen and careful dietary management.

gastrointestinal problems in teenagersGastrointestinal difficulties are often associated with stress or anxiety, illustrating the link between mind and body, and specifically the gut.  Abdominal pain, reflux or diarrhoea that become persistent can be successfully treated by diet. Teenagers can be affected by emotional problems and may experience restricted or disordered eating at some point. I offer specific dietary assessment and link with other paediatric colleagues including family therapists or psychologists when there is concern about an eating disorder.

Questions are welcome by contacting me directly, or of course to provide any feedback about this website.