Nucleus Accumbens And Neuronal Responses To Varied Dietary Intake

“Accumbens nucleus’ or the ‘nucleus accumbens septi’, is a part of the human brain. It is in the forebrain, and is also part of the basal ganglia (the part of your brain that generates movements, and is also involved in cognitive function, as well as dealing with emotional actions). Neuronal responses happen without our involvement, meaning they are subconscious. One of the best illustrations of a neuronal response to dietary elements is Ivan Pavlov’s Nobel prize-winning work dealing with what he referred to as ‘psychic secretions’. Pavlov determined that his dogs, which were fed at certain intervals, would start secreting saliva just at the appearance of his helper, who fed the dogs. They had been conditioned to expect food once the helper arrived. However, their response was subconscious. This is a neuronal response to food.

What is facsinating, is that there are individual differences in response to foods, based on their perceived reward, or…conditioned response. What is also fascinating, is that sleep deprivation INCREASES the neuronal response to unhealthy food (this is due to the hormone ghrelin).

If you have followed me so far, you can begin to see that ‘a carrot is not just a carrot’ to paraphrase Dr. Sigmund Freud. If an animal (i.e. humans) have been trained to expect something and enjoy a reward (again, via neurons/neurotransmitters) they will salivate different enzymes than other animals. There is also the issue of sense memories. If I have been trained to associate positive experiences with eating a Snickers® bar, whether due to dopamine release, socialization, or positive memories, not only will I be more likely to more frequently purchase the candy (especially compared to a food-naive individual), but I will actually emit anticipatory saliva, with different enzymes than a food-naive person will.

You can also hopefully start to see the parallels in diseases like schizophrenia, obesity, Alzheimer’s, autism, etc. due to their relationship with neurotransmitter and hormonal issues.  Take schizophrenia, which we once believed to be a behavioral disorder. We now know that it is a chemical imbalance in the brain. But, 90% of the serotonin in your body is produced in your digestive tract. So you are directly correlated to what you consume. Your mental health can be, and IS, altered by your diet.

Why do most diets fail? Hormonal responses. This has been widely studied, but the general public is still unaware of this basic fact. Insulin resistance, leptin resistance, downregulated enzyme and gene expression, high ghrelin levels due to sleep deprivation, et al. It has nothing to do with willpower. It has everything to do with conditioning and biochemistry. You can’t stop eating a cookie after dinner because you’ve CONDITIONED your body to expect a cookie. You are literally addicted to the timing of that glucose/fructose/sucrose. What happens if you try to skip it? Withdrawal. We all know the effects. It could be idiopathic postprandial syndrome (imagined low blood sugar) or it could ACTUALLY be reactive hypoglycemia (actual low blood sugar). It’s usually the former, but an HbA1C test or glucose tolerance test will give you an accurate diagnosis.

The parallels to depression (decreased serotonin receptor levels) and diet should be obvious now. If depression is, by definition, decreased serotonin receptor levels, and 90% of your serotonin is produced in your digestive tract…do I even need to draw the conclusion? The studies show this clearly. Not to mention the obvious logical conclusion that a vitamin and/or mineral deficiency, a SINGLE one, can cause a myriad of symptoms. It is scary to think what a poor diet, full of vitamin and mineral deficiencies, is doing to your brain and neurons.

Lines of cocaine

The brain of a cocaine addict has depleted, altered, dopamine levels. They got a massive flood of dopamine (which wasn’t allowed to be recycled) the first time they did the drug, and chase that high every time thereafter. Since the reaction is now expected, they will never meet the same dopamine response. Remember Pavlov’s dogs salivating at the sight of the helper? This is the same response. Dopamine (specifically D2) receptors in drug addicts are lessened. This is also the case for obese subjects. Same pathways, same diminishing returns. Only the obese person’s drug of choice is hyper-palatable food, which secretes insulin and dopamine, and contains no nutrients, no fiber, and has no satiating content (satiety is what makes you ‘feel full’ after a meal, and is directly related to the hormone leptin, and its proper functioning). This food is designed by chemists to trick your brain into eating more, and to creating a reward memory in your brain. Hence the “Coca-Cola® = Happiness” marketing campaign.

The drug industry has realized this (let me count the ways…) and have gone so far as to patent and trademark vitamins, like vitamin E, vitamin B6, and compounds that SHOULD be vitamins, like Coeznyme Q10. They want to be responsible for your brain to reward itself, and then keep coming back to them for the same dopamine hit. They know this, and the entire drug, supplement and processed food industry thrive on it. Not to mention low self-esteem (‘take this pill and be happy’), low body image (‘take this pill and lose weight’) and just about any neurosis imaginable. Originally, the word ‘vitamin’ stood for ‘vital amines’. ‘Vital’ because they are essential to the body. ‘Amines’ are organic compounds that contain a basic nitrogen atom with a lone pair. It now stands for ‘Flintstones Chewables®’. Sadly America has gotten dumber, and so has the world, which I would argue is largely in response to adopting our diet and principles. But what are some specific, POSITIVE compounds, that fight AGAINST disease and aging? We start with antioxidants.

Vitamin E comes in multiple forms, and is one of the most potent antioxidants imaginable. Antioxidants prevent cellular damage (diseases, aging, cancers…all linked to cellular toxicity/damage) by stopping oxidation from occurring. Reactive oxygen species (ROS) cause oxidative stress to cells, and antioxidants help stop this from happening. The more antioxidants in your diet, the less oxidative stress. You can obviously see the parallel that a small or non-existent amount of antioxidants in your diet will increase the speed of cellular damage, and its related effects (aging, cancers, disease, etc.) Discovered by researchers in 1922, who found a substance in vegetable oils that was needed for rat reproduction, vitamin E is actually 2 sets of 4 compounds. The tocopherols, and the tocotrienols. Alpha-tocopherol is the one the humans need to meet their daily requirements, and is most often found in food.

One advantage to vitamin E is that it does not accumulate in the liver, like other fat soluble vitamins. Vitamin E is technically a free radical, but is very low on the reactivity scale. It is dependent on vitamin C and selenium, as well as related to glutathione (the ‘mother’ of all antioxidants) and glutathione reductase. I like vitamin E as a recommendation and it is an undoubtedly an important antioxidant. But not as much as I like alpha lipoic acid, which is technically a supplement.

Alpha lipoic acid is made by the body, and its true advantage is that it is fat and water soluble. Meaning it can work in any part of the body, and even help to make other antioxidants active again. Autonomic and peripheral neuropathy have both been studied with alpha lipoic acid, and both conditions have seen improved results. Alpha lipoic acid works well for controlling blood sugar levels, and as such, is often recommend for sugar control and diabetes. Next we move to a vitamin with excellent health and cellular benefits.

One of the most interesting responses to dietary intake of a vitamin, is the response due to niacin, or vitamin B3. Researchers are finally beginning to understand that high doses of this vitamin can help with a variety of symptoms. According to this study: “Therapy with niacin (nicotinic acid) is unique in that it improves all lipoprotein abnormalities. It significantly reduces low-density lipoprotein cholesterol, triglyceride, and lipoprotein(a) levels, while increasing high-density lipoprotein cholesterol levels. This makes niacin ideal for treating a wide variety of lipid disorders, including the metabolic syndrome, diabetes mellitus, isolated low high-density lipoprotein cholesterol, and hypertriglyceridemia. Niacin is thought to work via the GPR109A receptor, and this  is a G-protein-coupled receptor. When a patient has colon cancer, this receptor is silenced.

The nucleus accumbens is the brain’s ‘pleasure center’. Lets examine what happens in the NAcc when we eat a high-carbohydrate food. Just like a drug addict experiences, research has shown that intense activity was experienced in the NAcc after ingestion of a high GI-load food. Sadly, just like Pavlov originally discovered, the NAcc response to cues of food, predicts obesity (the variable is your self-control). In the world’s current , hyper-stimulating, cortisol promoting environment, one must remove themselves and detach from food stimulus, to stand a chance against obesity. Since it is proven that weight loss rarely lasts, and is again, hormone-related.

When a healthier food is consumed, like kale, the NAcc reacts very differently. Stress can induce a predilection for NAcc rewarding foods. Coincidence? I think not. If drugs dampen D2 dopamine receptors, and obesity also dampens the receptors…doesn’t it seem obvious that hyper-palatable foods are dampening receptors, since they are stimulating the NAcc in the exact same way?

In a fascinating study of binge eaters, University Of Pennsylvania researchers determined that a method entitled ‘deep brain stimulation’ alleviated symptoms of binge eating, and in fact, caused binge eaters to change their behavior. This is an extremely significant finding, since we know binge eating seems to only be TRULY conquerable via altering dopaminergic pathways.

Though this is a surgical procedure, it does show hope for the millions of obese individuals in this country, many of whom feel like victims and helpless in their condition, which, left untreated, will no doubt lead to further complications and disease. This is also good news for those of us who are not obese, as our medical costs will likely not increase, since obesity now costs Americans more in healthcare than smoking.

Hopefully I’ve helped you understand the complexities of brain chemistry and food a little bit better today. As always, feel free to leave comments, questions, whatever you like.