You should only deprive your body of the nutrients provided by a food group if your health requires it – not because it’s fashionable, says Amy Giannotti.
It seems many people have forgotten the basics of healthy eating: to eat from each of the five food groups to meet 100% of our nutrition requirements. Why are we now intentionally eliminating food groups? Each food group is characterised by providing different nutrients. For example, ‘dairy and/or alternatives’ is our richest and most available source of calcium, as well as a good source of protein, iodine, vitamin A, vitamin D, riboflavin, vitamin B12 and zinc. ‘Grains’, meanwhile, especially wholegrains, are a rich source of carbohydrate, fibre, protein and B group vitamins, as well as a good source of iron, vitamin E, zinc, magnesium and phosphorus. There are more than 35 different nutrients, all with essential roles in the body. Different foods provide different nutrients. The amount of each nutrient we need is unique and, depending on our gender and stage of life, that amount, or recommended dietary intake, changes. For example, 1,000mg of calcium is recommended for US adults aged 19 to 50. In the US, women over 50 years require 1,300mg to compensate for the loss of oestrogen (a calcium transporter) produced post-menopause. Children aged 14 to 18 also require 1,300mg per day to support their growing bones. The recommended food group serves to match our nutrition requirements across our lifespan.
Tools and energy to build your house
We must appreciate that these nutrients are like our ‘tools’ to carry out vital functions of the body, and our ‘fuel’ comes from our macronutrients or energy-yielding nutrients (carbohydrate, protein and fat). It often seems that protein’s requirements are overestimated and the other tools, such as calcium, iron and B group vitamins, are neglected.
Grains and dairy
Wholegrains are little powerhouses, containing more than 26 nutrients and phytonutrients that help nourish and maintain health. According to the Grains and Legumes Nutrition Council, eating wholegrains daily is linked to a reduced risk of chronic disease, including cardiovascular disease, type 2 diabetes and certain cancers by 20-30%. It is also linked to a lower waist circumference, a lower risk of being overweight and a lower risk of weight gain over time.
Consumption of milk, cheese and yogurt is linked to a reduced risk of heart disease, stroke, hypertension, type 2 diabetes, metabolic syndrome and colorectal cancer, according to studies referenced in the Australian Dietary Guidelines. Regular dairy consumption is also linked to a healthy weight and has been shown to play an important role in sport, development of lean muscle mass and exercise performance.
Who should avoid what?
So, who should avoid dairy and gluten (found in wheat, barley, rye and oats)? Coeliac disease is an inherited medical condition in which the lining of the small intestine becomes damaged when exposed to even small amounts of gluten, which is a protein found in wheat, barley, rye and possibly oats. According to Coeliac UK, coeliac disease affects at least 1% in the UK and Europe; however, only about 24% are currently clinically diagnosed. A strict, lifelong gluten-free diet is currently the only recognised medical treatment. By eliminating the cause of the disease, a gluten-free diet supports the small bowel lining to repair and the symptoms to resolve. Individuals with coeliac disease will have been born with the genetic predisposition.
The major genes linked with susceptibility to coeliac disease are HLA-DQ2 and HLA-DQ8. A blood test (coeliac serology) screens for the disease itself. Coeliac serology measures antibody levels in the blood, which are elevated in people with untreated coeliac disease, due to the body’s response to gluten. A diagnosis of coeliac disease should not, however, be made on the basis of a blood test alone. A positive blood test always needs to be followed by a small bowel biopsy (sample) to confirm typical damage in the small bowel lining.
It is important also to note that gluten must be consumed in the diet for the antibody and biopsy tests to be accurate. The gastroscopy (for biopsy) is a simple day procedure done under light anaesthetic sedation, which takes about 10 minutes.
Cow’s milk allergy and lactose intolerance
Cow’s milk is a common cause of food allergy in infants (and is unrelated to being lactose intolerant). According to Allergy UK, “Symptoms suggestive of cow’s milk allergy based on self-reports vary widely and only about one in three children presenting with symptoms is confirmed to be cow’s milk allergic using strict, well-defined elimination and open challenge criteria. With these criteria, cow’s milk allergy is shown to affect between 1.8% and 7.5% of infants in the first year of life. This may be an overestimate, as Venter and colleagues confirmed cow’s milk allergy, using the double blind placebo–controlled food challenge for diagnosis, in only 1% of their population compared with a double prevalence of 2.3% using an open food challenge. Clinicians should therefore anticipate between 2-3% of children having cow’s milk allergy.” Treatment for cow’s milk allergy involves removal of cow’s milk and other dairy products from the diet and substitution with an appropriate formula for infants.
Lactose intolerance is caused by a lack of the lactase enzyme in the lining of the gut, which helps to break down lactose, the carbohydrate or sugar found in cow’s milk. Symptoms include diarrhoea, vomiting, stomach pain and gas, which are similar to some of the symptoms of cow’s milk allergy. Although this condition causes discomfort and sometimes embarrassment, it is not dangerous and does not cause rashes or anaphylaxis as with the cow’s protein allergy. Small amounts of cow’s milk are usually tolerated, and yoghurts and hard cheeses containing less lactose are usually tolerated more than cow’s milk. Skin or blood allergy tests are required for a cow’s milk allergy diagnosis but are negative for lactose intolerance. The diagnosis for lactose intolerance can be confirmed by a hydrogen breath test. For lactose intolerance, treatment may involve reducing or avoiding consumption of dairy products containing lactose and substituting them with lactose-free dairy products or alternatives. You’ve probably heard it said that “we are the only species to drink the milk of another species”. True, but humans are the first to do lots of things, including nurturing plants, cooking food, drinking coffee, fermenting grapes to make wine, exercising for fitness … does that mean they’re all bad?
Different people, same nutrient needs
We must appreciate we are all individuals with different health and ethnic beliefs, religions, food habits, experiences and taste preferences. Due to lifestyle factors, food preferences, availability, health status, activity levels and health and fitness goals, there is no ‘one size fits all’ for a diet or way of eating. However, we must not ignore that we are all the same species with the same basic requirements. Develop an understanding of your body’s requirements and appreciate the foods that will meet these. Consuming your food groups in the recommended amounts is a great framework for you to build on and personalise.
Where to next? Find out the different ways intermittent fasting affects male and female bodies HERE
Amy Giannotti is a dietitian, personal trainer, running coach and passionate foodie. Check out her e-book, Fit Fabulous Foodie, at eatingfit.com.au