Is Sugar Addictive?

For years it has been debated if sugar is addictive or not.  Recently it has been shown to have the same reaction in the brain as COCAINE.

So is it or isn't it?

Jordan Gaines Lewis, a PhD candidate at Penn State College of Medicine is here to explain exactly what happens to the brain when a person STOPS eating sugar.

Addiction:

Sugar is such an ingrained part of our food that we hardly even realize it's there.  Most of us prefer sweet foods over sour and bitter foods.  This is because our mesolimbic pathway reinforces that sweet things provide a healthy source of carbohydrates.  And, this is because of EVOLUTION.

In neuroscience, food is called a "natural reward".  In order for our species to survive things like eating, having sex and nurturing others must be pleasurable to the brain so that these behaviors are reinforced and repeated.

Evolution has developed the mesolimbic pathway, this is a brain system that deciphers these natural rewards for us.  When we do something that is pleasurable, the ventral tegmental area uses dopamine, a neurotransmitter, to signal the nucleus accumbens.

What helps us to decide if we want another bite of chocolate cake is the connection between the nucleus accumbens and the prefrontal cortex.  The prefrontal cortex also activates hormones that implant the idea that the cake we are eating is really good and makes us remember that in the future.  And, here we go back to evolution, when our ancestors went looking for food sour tastes meant "not yet ripe", bitter meant "alert - poison!", and sweet meant "ok!".

However, modern diets have changed beyond recognition from the fruit gathering days.  With huge amounts of processed and prepared foods in our diets means it is almost impossible to escape added or "hidden" sugars.  Over a decade ago, it was estimated that the average American consumed 22 teaspoons of ADDED sugar per day, adding up to an extra 350 calories.

Not long ago, an expert estimated that the average Briton consumes 238 teaspoons of sugar each WEEK.

These added or hidden sugars have turned us all into unknowing addicts.

Drugs such as nicotine, cocaine and heroin hijack the brain's reward pathway and make users dependent on them, increasing neuro-chemical and behavioral evidence suggests that SUGAR is addictive in the SAME WAY.

There are 4 major components of addiction: bingeing, withdrawal, craving and cross-sensitization (the notion that one addictive substance predisposes someone to becoming addicted to another).

All of these components have been observed in rats tested in laboratories for sugar as well as drug abuse.

A typical experiment works like this:  rats are deprived of food for 12 hours every day, they are then given 12 hours of access to a sugary solution and regular chow.  After a month of following this daily routine, rats displayed behaviors similar to those on drugs of abuse.  They'll binge on the sugary solution in a short period of time, much more than their regular food.  They also show signs of anxiety and depression during the food deprivation period.

Also, many sugar-treated rats who are later exposed to drugs such as cocaine and opiates, demonstrate dependent behaviors towards the drugs compared to rats who did not consume sugar previously.

Like drugs, sugar spikes dopamine release in the nucleus accumbens, the part of the brain that controls feelings of reward.

In the long term, regular consumption of sugar changes the gene expression and availability of the dopamine receptors in the brain.  Specifically, sugar increases the concentration of a type of receptor called D1, but decreases another receptor type called D2.  Regular sugar consumption also inhibits the dopamine transporter action, this is a protein which pumps dopamine out of the synapse and back into the neuron after firing.

All this means that over time, repeated access to sugar leads to prolonged dopamine signaling, greater stimulation of the brain's reward pathways and a need for even more sugar to activate all of the dopamine receptors.

In short, the brain becomes tolerant to sugar - and more is needed to attain the same "sugar high".

Withdrawal:

Some people give up sugar for short periods of time, say for lent.  A fellow graduate student who did this told Lewis that the cravings never disappeared but they did get easier to deal with after a week or so.

A 2002 study by Carlo Colantuoni and Colleagues at Princeton University - rats  who had undergone a typical sugar dependence protocol then underwent "sugar withdrawal".

They managed this by either food deprivation or treatment with naloxone, a drug used for treating opiate addiction which binds receptors in the brain's reward system and stops the craving for drugs.  Both methods for withdrawal produced the same physical problems including teeth chattering, paw tremors, and head shaking.  The rats treated with naloxone also appeared more anxious, as they spent less time on an elevated apparatus that lacked walls on either side.  Rats in sugar withdrawal also showed to be more passive in the forced swim test, preferring to float than to actively try to escape when placed in water, suggesting feelings of helplessness.

Obviously, these experiments in rats are fairly extreme, but they give us an insight into the neuro-chemical underpinnings of sugar dependence, withdrawal and behavior.

We humans have spent decades debating the existence of "sugar addiction".  There are accounts of people going through "sugar withdrawal" describing food cravings, which can trigger relapse and impulsive eating.  However, there are also countless articles and books about the boundless energy and new found happiness in those who have given up sugar for good.

So what will you choose?  Be a slave to the sugar industry, a drug addict?  Or, will you suffer withdrawal in the hope of a healthier, happier life?

I can help you improve your health.  If you would like to make an appointment with me either in person or via Skype, just send me an email to lucycarr@socialnutrition.com