Being full of whims and fancies as a child is all very well. But when capriciousness about food stretches into adulthood, it could hold serious long-term consequences.

Avoiding vegetables

I'm often appalled when readers say they want to lose weight or improve their health, and then say to me, “But I don’t eat any vegetables, so that’s not an option!” Many concerned parents also write to me about the problems they have persuading their children (of all ages) to eat vegetables.

Vegetables and fruit are probably the healthiest foods out there – and yet many of us grow up not eating them. They contain plenty of antioxidants such as beta-carotene and vitamin C, other so-called phytonutrients that protect us against a host of diseases, and dietary fibre that helps to lower cholesterol levels and promote bowel health.

An astounding number of people avoid vegetables or eat only one or two varieties (usually potato chips drenched in fat, which probably contain harmful trans-fatty acids). According to surveys done in the UK and the USA, French fries are the major vegetable, and often the only one, consumed by people living in these countries.

So, what are the long-term consequences of avoiding vegetables? Anyone who doesn't eat at least 3-4 servings of vegetables a day runs the risk of developing deficiencies of beta-carotene, vitamin C, protective phytonutrients and dietary fibre, which in turn can lead to heart disease, various types of cancer, diabetes and other so-called ‘diseases of lifestyle’.

But just by eating a variety of vegetables and having 3-4 servings a day, you can turn this situation around and prevent many ills. Remember that it’s good to eat one dark yellow or dark green vegetable (pumpkin, butternut, carrots, sweet potatoes, broccoli, silver beet or spinach) for beta-carotene, and at least one vitamin C-rich vegetable (all the vegetables in the cabbage family, including broccoli, cauliflower, Brussels sprouts, spinach, capsicum or chili) every day.

To get your children used to eating vegetables, introduce vegetables to your baby before offering fruit during the weaning period (after the age of 6 months). Persist in offering your baby small portions (1 teaspoon at a time) of the same vegetable until he or she eats it. Then start with the next veggie. By doing this, you'll foster a healthy habit for the rest of your child's life.

For those children (and adults) who still have trouble getting enough vegetables in, you should seriously consider a multivitamin to plug any nutritional gaps that develop as a result. For adults, a daily multivitamin may suffice, whilst for children, there are a number of 'kid-friendly' multivitamin options.

Avoiding milk and dairy products

Some readers proudly inform me that they've cut out milk and dairy products to lose weight. This is particularly popular among teenagers and young women, who ironically need the calcium in milk and dairy products the most at a time in their lives when they're supposed to be filling up their body stores of calcium. Why they should do this, remains a mystery.

Others readers were fussy about drinking milk or eating dairy products as children and, as a result, have never learnt to like dairy foods.

Years of avoiding calcium-rich foods will inevitably lead to low bone density, which results in osteoporosis. This is one of the most debilitating diseases that affects older people of both sexes, but is much more common in women.

Recent research has indicated that diets rich in calcium derived from low-fat milk and dairy products like yoghurt actually promote weight loss.

So, if you want to lose weight, don’t cut out milk and dairy products. Just have the low-fat varieties like skim or fat-free milk to ensure that you obtain the calcium you need for good health – without the fat. Getting enough dietary calcium can be tough - in order to get your full RDI of calcium from milk, you need to drink 3 - 4 glasses. SO even if you are eating alot of cheese and drinking alot of milk, a calcium supplement can be helpful to boost daily calcium intake. Make sure you are getting sufficient vitamin D, as your body needs vitamin D to absorb calcium.

If you have to avoid dairy products because of lactose intolerance or milk protein allergy, make a plan to use soya milk that has been fortified with calcium or use a daily calcium supplement.

Excess energy intake

Another bad eating habit that can develop over several years is overeating. This can be gross indulgence or just taking in slightly more energy than your body requires over a period of months and years. While gross indulgence will rapidly lead to weight gain and fat deposition in all the wrong places, even a small excess of energy intake will eventually cause inexorable weight gain.

This type of weight gain isn't caused by metabolic problems, but by the simple fact that the person in question eats more than he or she should be eating. It could be that slab of chocolate every day or indulging in junk food on a regular basis.

It takes as little as an extra 275kJ a day to pile on 1,5kg in 6 months or 3kg per year. Little lapses are forgivable if they don’t occur every day, but unfortunately most people do get into the habit of having that extra piece of bread with dollops of butter every day, and before they know it, they've gained weight.

So, think about the consequences when you visit the fridge or eat that extra slice of chocolate cake.

Eat a variety of foods

I could go on and on. There are so many health problems associated with poor dietary habits and avoidance of certain foods or whole food groups for long periods of time. This includes constipation if you eat too little fibre, or iron or vitamin B12 deficiency anaemia if you don’t eat any foods derived from animals.

The first and most important Food-Based Dietary Guideline is: “Eat a variety of foods”. Keep this in mind, because it encompasses the principle of eating foods from each food group every day – even if you're on a tight budget.

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