The number of additives in our modern day food is astonishing, and for some people they can have serious health effects.

However it also seems that some of the so-called natural products may be just as bad for us.

We've been told to steer clear of foods riddled with artificial colours and flavours, and for good reason.

• Natural sugar alternative
• High chemical levels in meat
• Toxic chicken warning

Frances Costanzo has severe anaphylactic reactions to any products that contain MSG or flavour enhancers.

And so after a number of serious attacks she has made a point of picking products that contained only natural ingredients.

"It said ‘all natural’, ‘no MSG’ and ‘no flavour enhancers’, and because it says ‘no MSG’ and ‘no flavour enhancers’, I bought it," Costanzo said.

But that was no guarantee. After eating an artificial free vegetable stock, she almost died.

"As I was sitting down I started coughing. I took some ventalin but it didn't help. The coughing got worse, my throat felt tight, I was starting to get dizzy," Costanzo recalled.

Sue Dengate is the founder of the Food Intolerance Network. She says many people choose products containing all natural ingredients believing them to be a better option.

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"There are some natural colours, flavours and ingredients that can cause as many problems as artificial colours and flavours," Sue said.

While it is a natural ingredient, it can be just as potent.

Food scientist Howard Dengate says consumers are being fooled by manufacturers who are replacing MSG and other nasties with these natural alternatives.

A popular chicken instant noodle pack that says ‘no added MSG’ has flavor enhancer 620, which is glutamic acid. As soon as it arrives in the food, it’s MSG - it's actually the same stuff.

While it appears to be healthier, natural doesn't necessarily mean identical to nature.

"Hydrolised vegetable protein and yeast extract, they are boiled up with hydrochloric acid and neutralised with hydrochloric soda," Howard explained.

In fact we need to be just as wary of some natural additives as we do of artificial ones.

Emma Lyndon noticed dramatic changes in her three boys after they ate certain foods.

"Tom, my eldest, who’s nine, he used to have a lot of trouble sleeping, settling at night. He said his mind wouldn't stop moving,” Lyndon said.

While creams and medications treated the symptoms she couldn't get to the crux of the problem.

According to Sue natural colour 120 is one of the biggest instigators which is added to many popular kids snack foods.

"120 is a natural colour that, because it’s made from crushed beetles, and therefore can have protein, can cause true food allergies," she said.

160b or annatto is another natural colour to avoid.

"160b in my opinion is one of the worst additives on the market because it can cause food intolerance reactions and it can cause true allergies, because it is made from a seed coat, and contamination for the seed can cause the allergies," Sue explained

160b is found in a variety of foods, including yoghurts, ice-cream, lollies and soups. It can cause some serious side effects.

They include irritability, restlessness, inattention, sleep disturbance, as well as physical problems such as stomach aches, headaches, asthma, and itchy skin rashes.

• 102 tartrazine
• 104 quinoline yellow
• 110 sunset yellow
• 122 azorubine, carmoisine
• 123 amaranth
• 124 ponceau, brilliant scarlet
• 127 erythrosine
• 129 allura red
• 132 indigotine, indigo carmine
• 133 brilliant blue
• 142 green S, food green, acid brilliant green
• 143 fast green FCF
• 151 brilliant black
• 155 brown, chocolate brown

• 160b annatto, bixin, norbixin

• 200-203 sorbic acid, potassium & calcium sorbates
• 210-213 benzoic acid, sodium, potassium & calcium benzoates
• 220-228 sulphur dioxide, all sulphites, bisulphites, metabisulphites
• 249-252 all nitrates & nitrites
• 280-283 propionic acid, sodium, potassium & calcium propionates

• 310-312 all gallates
• 319-321 TBHQ, BHA butylated hydroxyanisole, BHT butylated hydroxytoluene

• 620-625 glutamic acid and all glutamates, MSG monosodium glutamate
• 627 disodium guanylate
• 631 disodium inosinate
• 635 ribonucleotides
• Yeast extract, HVP HPP hydrolysed vegetable or plant protein

• No numbers since they are trade secrets

• Food Intolerance Network - www.fedup.com.au