Do you know what nutritional food is? Every day a new 'super food' emerges, promising everlasting youth and good health, while something you thought was 'healthy' is discredited. To help you identify the truth, I'm busting some of the common nutritional food myths:

1. 'Fat makes you fat'
Fat gets a bad press. And, where greasy chips and sticky cakes are concerned, that's probably justified. But it's important to remember that not all fats are made equal. Some fats - like those found in nuts, seeds, avocados, eggs, oily fish like salmon and mackerel, coconut oil and olive oil - are not only incredibly good for you, but an essential part of our diets. They will make you look younger and help keep you lean and healthy, as well as help you regulate a host of vital processes in your body. So don't shy away from fat, just be choosy which ones you eat.

2. 'Organic is always healthiest'
The jury is out as to whether the 'organic' label on an increasingly wide range of foods and groceries is really a marker for better nutritional value. There are some non-organic foods that deliver a quite scary amount of nasties into your body, but actually others are less of a concern.

Where meat, dairy and fresh produce (fruit and vegetables) are concerned, my personal preference is for organic, because it ensures that pesticide, hormone and other residues are minimal. In the case of animal products, it also gives a level of assurance regarding the ethical and welfare credentials of the producer.

But organic isn't the only label to look for - in fact most great foods don't have a label...

Seasonal, locally grown foods are likely to have minimal amounts of chemicals added and fewer food miles, and so if the choice is between a package of green beans 'organically grown' but then harvested too early, shipped thousands of miles, chilled, stored or displayed for days or even weeks before they reach your plate, then I'd recommend the local greens, albeit without the organic certification.

There are some fruits and vegetables that typically absorb large amounts of pesticides during their production, with apples, sweet bell peppers, celery and peaches among the worst offenders. These items, along with many salad vegetables and soft fruits, are the ones you want to choose organic if at all possible.

However, produce with very thick skin, or skin that is removed before eating, such as onions, grapefruit, pineapples or avocados are less likely to contain nasties by the time you eat them. Cabbage, eggplant, mangoes and asparagus are also considered pretty 'clean'*.

It's worth opting for organic when your budget and your shopping choices allow, but when they don't, go for the lower risk produce and choose local and seasonal, and 'free range' or 'grass fed' meat, dairy and eggs.

3. 'Drink eight glasses of water a day'
Yes, hydration is your friend! But there is no real evidence to support the hypothesis that eight glasses of water a day is the optimum level. Hydration isn't all about pure H2O either, other liquids like coconut water, fruit juices, herbal teas, - even normal tea and coffee in moderation - help to give your body the water it needs.

Hydrating foods - like green salads, red peppers, cucumbers, celery, grapefruits and apples - also contribute. The exact amount of water you need to hydrate your body varies all the time and it depends on lots of factors like your size, how active you are, and the heat and humidity in the environment.

4. 'Egg yolks are bad for you'
Egg yolks got panned in the past by studies that strongly linked dietary cholesterol to blood cholesterol. Recent research shows that the connection is misleading. Banning egg yolks from your diet means you miss out on a highly nutritional, natural food and a great source of protein and essential fats.

One yolk contains half of the daily requirement of chorine, which is an essential nutrient for the brain. Eating eggs for breakfast is also a great way to fill up with protein and 'good' fats - keeping you from overeating during the day.

5. 'Fried food is always unhealthy'
If you use 'healthy' oil, like coconut oil, and heat at the right temperature, then frying food at home is perfectly healthy, especially if you're making a stir fry packed with delicious nutrient-loaded vegetables and maybe some lean meat or fish. Coconut oil is especially good - it retains its full nutritional value when fried at high temperatures (unlike olive oil - save your good olive oil for drizzling!). The optimum frying temperature is 375 degrees - higher or lower makes food absorb too much oil.

6. 'The sugar in fruit and sugar in cakes is the same'
Technically sugar reacts in the same way inside our bodies, whether it originated in a chocolate brownie, or a kiwi fruit. It's broken down into glucose for energy and the excess stored as fat.

But, that's where the similarity ends: sugar from fruit gets absorbed slowly, while simple sugars increase blood sugar to levels that cause arteries to age. The other major difference is that fruit sugar has good-for-you packaging, full of vitamins, minerals and phytochemicals that do lots of good things for our bodies. These benefits are too-good-to-miss, despite the sugar that comes as part of the (all-natural) package.

More information here on choosing good fats and reducing the chemicals and sugar in your diet.

*The Environmental Working Group (EWG) shoppers guide to pesticides in produce

Follow Wendy Powell on Twitter: www.twitter.com/mutusystem