We all know it’s important to eat our greens - but how can you be sure the vegetables on your child’s plate are packing all they should? Read on for a fresh take on garden-variety questions

Are all vegetables equally nutritious?

No, but each and every one is worth eating. Over 200 separate studies have confirmed that a diet high in fruit and vegetables helps prevent heart disease and cancer. And that means more than just broccoli, peas and carrots. Branch out and your body will absorb vitamins, minerals, fibre or phytochemicals. Besides, all raw vegetables are fat-free, with one healthy exception - the avocado. It is loaded with good-for-you monounsaturated fat and is an excellent source of folate (a B vitamin) and vitamin C. Top in vitamin C include sweet peppers, Brussels sprouts, kohlrabi and asparagus. Looking for fibre? Turn to sweet potatoes, green peas, parsnips, corn and artichokes. Ribbon holders in beta carotene include carrots, kale, squash and romaine lettuce. While some veggies outrank others in certain nutrients, food scientists are the first to admit that they’ve identified only a fraction of the beneficial elements found in vegetables. So reach for a rainbow of plant foods, rather than that mythical miracle food, and you’ll get great benefits.

Is there a way to make sure you won’t lose vitamins and minerals during cooking?

Nutrients are apt to flee when you start to cook. They just aren’t fond of the heat, oxygen and water involved in the process. But, good food preparation practices you can retain 75 to 90 percent of the vitamins and minerals found in raw, unprepared vegetables Vitamin C (found in tomatoes, cabbage and sweet peppers, among others) is both water-soluble and heat-sensitive. Two other key veggie nutrients, folate and potassium, are also water-soluble. If you reduce water and cooking time, those nutrients will have less opportunity to dissolve and disappear. Try steaming, microwaving or stir-frying for best results. If you must boil, use the smallest amount of water possible and wait until the water has come to a full boil before adding vegetables. Not all cooking is the enemy, though. When you slowly braise vegetables in liquid, make soups, or puree foods using a vegetable’s cooking liquid, you capture potential nutrient escapees in every spoonful. Boost iron levels in spinach, legumes and potatoes by cooking with a cast-iron pan. Add some vitamin rich tomato sauce or orange juice, and you’ll absorb more of the iron found in these foods. Always store fresh-cut vegetables in airtight containers in the fridge to stem nutrient loss.

Is it better to eat veggies raw or cooked?

It’s best to eat a balance of both. Eat them raw to get maximum nutrient content plus heat-sensitive enzymes, which aid in digestion and tissue repair. But eat an ample supply of cooked vegetables, too. Three cancer-fighting phytochemicals - lycopene, beta carotene and quercetin - can all be absorbed better from cooked vegetables. While raw tomatoes contain lycopene, you’ll absorb higher levels from cooked tomatoes - whether in ketchup, tomato sauce or tomato juice. Steaming carrots until tender-crisp can double the amount of beta carotene your body can absorb. Ditto for spinach and broccoli. Most kids aren’t fond of the spicy bite of raw onions and, fortunately, quercetin is better absorbed once onions - or another source, Brussels sprouts - are cooked.

How should I store vegetables to keep them fresh?

A vegetable’s favorite home is not necessarily the crisper drawer in your fridge: Sweet potatoes, baking potatoes, winter squash, rutabaga, garlic, ginger and storage onions (yellow, red and sweet) all keep best in a dark, cool cupboard. Keep fresh onions such as leeks, green onions and chives in the fridge. Remove any bands or twist-ties. Wrap green onions in a dry paper towel and store in a plastic bag in the crisper. Chives spoil quickly in the fridge, but freeze well when chopped finely.

Some veggies are really fruit in disguise. Tomatoes, avocados and plantains belong in the fruit bowl. Once fully ripe, they can spend a brief sojourn (one to three days) in the fridge. All leafy greens - be they lettuce, arugula, bok choy, collards, kale, escarole, spinach or watercress - will stay perkiest if you remove rubber bands or twist-ties, wrap them loosely in a few sheets of dry paper towel and store in a perforated plastic bag in the crisper. Broccoli, cauliflower and Brussels sprouts are best stored in a perforated plastic bag in the crisper, but lose flavour every day they stay there. Mushrooms and bean sprouts call out for a paper bag - they’ll turn slimy in plastic. For beets, carrots and radishes, remove the greens and keep in a plastic bag in the fridge. But beware of other crisper companions: A loose apple can turn your lettuce limp and carrots bitter due to the fruit’s natural emission of ethylene gas. Keep your apples under zip-lock in a closed plastic bag in the fridge but out of the crisper, and your veggies will thank you. Since vegetables contain water-soluble vitamins, avoid storing celery, carrots or asparagus in water.

Which contains more nutrients: fresh, frozen or canned?

Conventional wisdom tells us that fresh is best. Yet the fact is, frozen and canned vegetables have been getting a bad rap. This is why: Nutrients start to leave vegetables the second they are plucked from the ground. Fresh vegetables - especially during the winter and always in the case of imports - spend several days in transit before reaching a store. Then they’re likely to sit a while, storeside, followed by a languid day or two in your fridge. A week may pass from farm to stomach. Frozen and canned foods, on the other hand, are processed the day a vegetable is harvested. A 1995 study from the University of Illinois found that canned and frozen foods were just as - and sometimes more - nutritious as fresh.

Should I worry if my child eats only one kind of vegetable?

If your child will only eat mashed potatoes or sweet peas, do yourself a favor and don’t worry. When parents push the panic button over food, the result is rarely positive. Besides, if Junior isn’t crazy about broccoli but loves to munch mango, he’s getting many valuable nutrients from fruit. In fact, most fruit is comparable to vegetables when it comes to vitamins, minerals, fibre and phytochemicals. Theories abound on why kids and veggies don’t always mix. We know that children taste flavors more acutely than adults, with 25 percent of kids falling under the super-taster classification. These kids are less likely to embrace strong-tasting veggies like broccoli or rapini.

What’s the best way to handle and slice onions?

Do you slice and weep? Stop the tears by freezing peeled onions for ten minutes before you chop, rinsing the knife a few times between slices. To remove onion and garlic smells from the hands, rub your wet hands against the stainless steel portion of the kitchen faucet and voila! The sweet smell of success.

Is there any nutritional value in a french fry?

If your kids flip for fries, you’ll be glad to know they are a source of vitamin C, thiamin and niacin. Problem is, those nutrients come in relatively small amounts and are generally bathed in fat. But childhood is not the time to be counting fat grams. Children need fat to grow. But as with everything, moderation is the name of the game.