Good nutrition is at the heart of every healthy child. But it may not be as simple as just eating five-a-day.

Paediatric neurologist Dr Maya Shetreat-Klein believes the fundamental ingredients children need to be healthy and happy come from nature, and that consuming processed foods and pesticides, plus relying too much on medication, can exacerbate numerous different conditions from ADHD and autism to ulcerative colitis, Crohn's disease and rheumatoid arthritis.

Healthy soil

In her new book Healthy Food, Healthy Gut, Happy Child, Dr Shetreat-Klein argues that the old adage, 'You are what you eat' should really be, 'You are what your food eats', explaining that because both we and the animals eat plants, "we are only as healthy as the soil our food is grown in".

For this reason, she says children should eat organic food if possible, pointing out that a growing body of research shows that pesticides affect children before they're even born and are linked to subsequent autism and ADHD, and childhood pesticide exposure has been linked to obesity, asthma, cancer, food allergies and delayed or abnormal development.

She stresses: "Eat organic or biodynamic wherever possible. Buying organic food is healthier."

Food reactivity can play a role in every health condition, she says, and often-unrecognised food allergies and intolerances "are symptoms of an unwholesome food system depleted of nutrients and filled with processed foods and additives. They are also symptoms of a disrupted digestive tract and imbalanced immune system".

Immune response

Dr Shetreat-Klein, who practises in New York, explains that children who eat food that's processed in ways their bodies haven't evolved to recognise are more vulnerable, and more likely to become allergic or chronically ill.

"Consider that an allergic child has an immune system that's occupied with attacking things it shouldn't - like food, or itself - so it may not be able to dedicate the resources to fight infection effectively," she says.

"On the other hand, children who are well-nourished with nutrient-dense foods grown in rich soil, have the tools they need to be resilient in the face of infection and other stressors. These children are even more likely to be healthy if they're given opportunities to be outdoors and exposed to varied amounts of diverse microbes, which strengthen and balance their immune systems.

"And ultimately, each time a child overcomes an infection, it's stronger and more resilient the next time one comes round."

Elimination diet

The neurologist says removing foods that may be causing a problem is the first step to improving a child's health, and if they look, feel or act differently after eating a particular food, or show symptoms like being ill, aggressive, congested, or they develop a rash after eating it, eliminate it from their diet.

Keeping a food diary for the child may help, and if there's any doubt about a food, try elimination and then reintroduction after about a month to see if there's any difference in symptoms.

Bad medicine

Dr Shetreat-Klein also believes that too much medication, and excessive cleanliness through bleaching and hand sanitisation may have a negative impact on children's health.

She points out that research shows children exposed to bleach have more infections, with a 20% higher risk of coming down with flu, and hand sanitisation contains the chemical triclosan which can disrupt endocrine function in the body and increases the risk of asthma, eczema and allergies.

In addition, she says that while medication is crucial in a crisis, many studies show repeated courses of antibiotics, especially in children, have a detrimental impact on future health, and even over-the-counter medications can interfere with the body mounting its own robust immune response to problems.

Tip-top terrain

The gut is a vital part of the body's 'terrain', says Dr Shetreat-Klein, and like a rich soil, it's healthiest when bathed in abundant nutrients and diverse microbes. Fewer types of microbes make it more likely for one type to dominate improperly, which can lead to gastrointestinal problems, she explains.

Children need to play out and get dirty, she says, and stresses: "Dirt and nature reach into children's bodies and minds through their food and play.

"A healthy terrain is dirty, messy, complex, and doesn't come in a pill or a package. It's the very messiness of the natural world that makes us so resilient, which is the key to robust health."

Dr Shetreat-Klein's healthy diet tips:

:: Eat fresh and organic, and keep peel on where possible.

:: If you can't afford organic food, avoid fruit and vegetables that consistently test high for pesticide residue, including apples, strawberries, grapes, celery, peaches, spinach, cucumbers, cherry tomatoes, potatoes and peppers.

:: Read food labels and try to avoid preservatives, food dyes, artificial sweeteners etc.

:: Avoid tuna because of mercury levels.

:: Give children plenty of pasteurised free-range eggs.

:: Eat only organic, pasture-raised meat.

:: Eat organic seeds, grains, beans and nuts.

:: Make easy, parallel food swaps, eg. instead of a packet of flavoured rice, buy plain organic rice and flavour it yourself.

:: Heal the gut with aloe gel, bitters and teas such as chamomile.

:: Balance the immune system with spices like ginger and turmeric.

:: Healthy Food, Healthy Gut, Happy Child by Dr Maya Shetreat-Klein is published by Bluebird on February 11, priced £14.99.

ASK THE EXPERT

Q: "I'm a bit of a technophobe and while I know it's important to make sure my kids are safe when they're online, I'm not really sure how to go about it. Have you got any tips?"

A: Secretary of State for Education Nicky Morgan says: "As a parent myself, I completely understand that children's access to the internet can be difficult to monitor and that the constantly changing nature of technology can be daunting. Thankfully, there are a few basic tips that you can follow to reduce these risks. Sites like ParentInfo (parentinfo.org), which has been set up with the support of the Government, ensure that parents are aware of current and changing issues and are equipped with all the relevant information they need.

"One of the key ways we can ensure our children remain safe is to encourage an open dialogue around the subject, set boundaries and, if necessary, restrict access for an agreed period.

"In addition, arm your children with advice. Safer Internet Day (February 9) is a great opportunity to talk to children about how they use the internet. Simple steps such as only talking to people they know and being careful about uploading videos or pictures may seem obvious as an adult, but may not be something children even consider."

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