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Open wide: are ‘healthy’ food choices making us sick?

The browning of apples illustrates how natural sugars in foods modify proteins and amino acids. quinn.anya/Flickr

Educated, wealthy and living longer than ever before – or are we? Have you noticed that despite people often making healthy food choices, we are developing chronic diseases at much higher rates?

A number of these chronic diseases involve the the body turning on itself (autoimmunity). They include type 1 diabetes, coeliac’s disease, thyroid diseases, allergies and rheumatoid arthritis.

All of these are considered to be diseases of so-called wealthy nations. And we are still learning about why our bodies are rejecting our food and lifestyle choices and leaving a wake of diseases for us to combat.

What’s on your plate?

We want to have access to all types of food, such as strawberries and asparagus, even when they’re out of season. In order to deliver, the food industry develops ingenious ways of obtaining, preserving and sustaining popular food choices.

But this often comes with more than one price.

Antioxidants, vitamins and amino-acid content, for instance, all decrease over time and with processing and cooking.

There can also be modifications to nutrients within the food, which can lead to the “ageing” of food. These alter the structure of proteins, changing the way foods are absorbed in our gut.

One particular chemical process, which occurs during food “interference” via processing and storage, is called advanced glycation. This happens when natural sugars found in foods modify proteins and amino acids.

A rapid version of this chemistry is seen in the browning of an apple upon peeling or cutting it.

The capsicum travels a long way to get to your dinner plate. ms.Tea/Flickr

We know that advanced glycation has increased in our foods as a result of increased food processing and a migration to faster cooking methods such as frying. Coincidently this has occurred over the same time period as the increase in chronic diseases.

Let’s take the humble capsicum. Before it reaches the kitchen, it’s often been in cold storage; it’s been gassed to ripen it, irradiated (if from overseas) and polished for a better shine.

Each of these processes leads to irreversible cross-linking of nutrients, which changes their structure.

So, instead of seeing a capsicum with lots of vitamin C, our body has a case of mistaken identity. The changed proteins and amino acids fool our bodies into thinking it’s trying to digest a new vegetable.

Our “meet-and-greet team”, the immune system, becomes a bouncer instead of the host and tries to throw this unknown protein or vegetable out the door by treating it as a foreign invader, such as bacteria.

This less-than-warm greeting is remembered for the next encounter where the reaction is even less friendly since cells and antibodies which recognise the “foreign” food proteins are already present and ready to do battle.

It’s a bit like certain foods have put on a disguise.

The road is long

So what happens to our “healthy” food from the time it leaves the farm or market garden?

Take the humble wheat grain. It gets heated, squished, fermented and sometimes irradiated before it becomes breakfast cereal.

Low-fat yoghurt is powdered and reconstituted, then sugar is added.

Essentially what’s happened is that a big moustache and sunglasses have been added to these natural products – no wonder our immune system is a bit confused.

Deep frying food changes the proteins in them. VirtualErn/Flickr

Apart from being created during the processing of food, advanced glycation can also take place during certain cooking methods, particularly cooking at high temperatures.

Our love of rapid cooking techniques such as frying hasn’t helped. The somewhat full-circle return of the slow cooker, which minimises protein modification during cooking and takes just minutes to prepare dishes, may offer a lifeline for our time-poor community.

So is this epidemic of autoimmunity just a case of social evolution winning a race against Darwinian evolution? Has our desire for food convenience hit a road block within our genes?

We suspect so.

The very fact that we live in a cleaner environment may be contributing to the rise in autoimmune illnesses by limiting our exposure to dirt, fungi and other natural bugs.

These bugs help the immune system to relax and allow in a more diverse range of “friends” into our body.

Our genetic code (DNA) has a handbook, which instructs the immune system about all such friends we have seen over generations and how we’ve dealt with them.

In fact, our genes may instruct our bodies to prefer familiar foods containing proteins and nutrients we have eaten for a very long time.

This is a bit like having a familiar face on the dietary proteins that our immune system recognises, which stops them from being treated as foreign invaders.

Curse of affluence?

What’s also puzzling is why people in countries with lesser wealth and less hygiene – developing nations – don’t get this group of autoimmune diseases.

As it happens, these nations often have no way to preserve food and sustain supply. Unbeknown to them, these limitations may be preventing increases of this group of diseases.

There’s now scientific proof that modifications of our everyday healthy food by storage and processing, can affect the incidence of autoimmune diseases.

Growing your own vegetables may be one way to eat truly healthy food. Mountain/\Ash/Flickr

Indeed, it may be time we took a serious look at how we can get fresher food on our table faster, by sourcing local producers and eating seasonal foods.

Another lesson is that we should be lobbying regulatory authorities to ensure that food labels include the physical processes which have been performed on the food and not just the additives.

Perhaps an index akin to “human interference factor” should be introduced.

Maybe in our fast-paced and sometimes sterile world, we need to learn some lessons from the past where we were not afraid to slow down to grow our own vegetables and stock animals and share these with our neighbours over a good local wine.

Why not turn your hand to your own vegie patch to grace your table with homegrown vegetables? Scared of a little dirt?

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