It's the first week of school holidays, and oblivious to your fraying nerves, the kids have converted the living room into a racetrack. "Five more weeks to go," has become your mantra du jour, but with more time ahead of you than behind, the ideas file on 'keeping the kids calm' is rapidly thinning out.

For naturopath, professional speaker and author of Calm Kids Jennifer Jefferies, toning down manic behaviour in what she terms 'go-fast' kids is a matter of good nutrition and a balanced approach to diet.

Through examining diet and running hair tests from her 15-year-old Townsville practice, Jefferies observed that zinc to copper imbalance is a major cause of hyperactivity in children. Another finding was the way calcium and magnesium level ratios affected sleep patterns.

"If they're low in calcium compared to magnesium, they might have trouble getting to sleep, and if they're low in magnesium in relation to calcium, they may have trouble staying asleep," Jefferies says.

Her remedy? For calcium deficiencies, have a glass of milk before bed and make sure they're eating enough dark

Zinc rich foods

• seafood
• seeds and nuts (especially brazil nuts)
• pepitas (pumpkin seeds)
• Copper rich foods
• chocolate
• grapes

green vegetables. And for a magnesium boost, opt for nuts and seeds ground up and served in a tempting afternoon smoothie.

Also a devoted aromatherapy advocate, Jefferies recommends calming kids down by burning oils before bedtime. While lavender is "often great", go-fast kids normally require heavier oils like sandalwood or vetiver, she says.

Longer term strategies for evening out energy levels and improving overall health involve developing positive eating habits. "I had one woman come into my clinic and say, 'My little girl will only eat sausage rolls.' It's really simple: stop buying them." Once you leave foods like meat pies and sweet treats out of the fridge, kids eventually get hungry and eat something else, says Jefferies. "I know one little girl who thinks it's normal for kids to eat broccoli dipped in hummus for morning tea. Her first five years have been spent building a strong foundation of nutrition."

Jennifer Jefferies' tips for lunch box snacks

• Low-fat yoghurt tubs with loose sultanas and nuts for them to add
• Cute vegetables like cherry tomatoes and sweet capsicum slices
• 100% fruit juice
• Water stored in a water bottle of their choosing
• Orange or mandarin wedges
• Low fat cheese cubes

When kids return to school, keep lunches fun and inviting, she advises. "Rather than tomato sandwiches which you know are going to go soggy, give them half a dozen cherry tomatoes and cheese cubes." Also try opting for compartmentalised lunch boxes to pique kids' interest. "Kids like interactive things. Let them put foods together so they don't get bored." And instead of going for white bread sandwiches, choose wholemeal tortilla wraps or buns.

Jennifer Jefferies' ideas for school holiday calm

• Keep a stash of car games for long trips: when kids get bored, they get wound up
• Use essential oils for long car trips, such as vetiver with a drop of peppermint, so they're mentally stimulated but not manic
• Create a 'hat of ideas'. Write activity suggestions on pieces of paper, scrunch them up, throw them in the hat and let kids take it in turns to draw an idea out each day of the holidays
• Prepare snacks such as smoothies with ground up nuts and seeds, sultanas and fruit. Remember: everything in moderation
• If you think your child might have a copper and zinc or magnesium and calcium imbalance, see a naturopath for tailored advice

Find out more about Children's Health Conditions.

Feel better. Eat Well. Stay fit. For all the health information you and your family need, subscribe to Blackmores' fortnightly wellbeing newsletter. As well as news and feature stories, receive seasonal recipes, fact files, expert health tips and more (without spending a cent).