Substance use disorders (formerly referred to as substance abuse) such as alcohol, cocaine, or cannabis use disorder to name a few, can negatively impact health, both physical, and specifically, brain health.
The use of substances can lead to poor overall and nutritional well-being in a few ways such as leading to a decrease in eating, increased loses of nutrients (excess excretion), decreased absorption in the digestive tract due to related damage, increased requirements for detoxification, and tissue repair and altered nutrient metabolism.
Substance use and brain health
Alcohol use disorder is a surprisingly underappreciated cause of brain damage, cognitive impairment, and dementia. There are a few ways in which alcohol can impact neuroanatomy and function. Alcohol can lead to nutrient deficiencies for the reasons mentioned above including thiamin (vitamin B1) deficiency, increased inflammation, and lower amounts of the omega-3 DHA in the brain (1).
Some postmortem brain omega-3 fatty acid and DHA studies have looked at the impact of chronic alcohol use on brain structure. They showed substantial losses of omega-3 from brain tissue and demyelination of neurons (when the fatty coating that envelops neurons is damaged) in chronic and heavier drinkers (1).
Omega-3s and DHA in particular offer neuroprotective properties against alcohol’s negative impact such as reducing neuroinflammation, increased cerebral circulation, and providing support via metabolites of DHA and their ability to support the way brain cells ‘talk’ to each other (1).
Because the omega-3 fats EPA and DHA have been associated with lower rates of dementia and given the increased risk for alcohol-related cognitive decline, it would be worthwhile knowing if omega-3 could offer protection from developing dementia.
A team of researchers exposed cultured brain cells of rats to high levels of alcohol on their own or in combination with DHA. The omega-3 fatty acid protected the brain cells from damage by alcohol, a whopping 90% reduction (2).
While it’s impossible to say that this will happen in the human brain to the same degree, it’s consistent with other research which suggests a neuroprotective and beneficial role of omega-3s.
EPA and DHA may also offer a benefit in those with substance use disorders as it relates to emotion regulation. There’s an understood association between aggressive behaviours and substance use.
Of course, there are lots of different reasons to explain this but given that substance use, more often than not, is predictive of poor dietary intake, some of the aggression could be related to an insufficient intake of nutrients known to be involved in mood regulation.
Omega-3, addiction, and aggression
In a small study of subjects who had a history of aggressive behaviour and problems with the law, subjects were randomized into one of two groups. The treatment group was given 3000 mg of EPA and DHA combined. After 3 months, EPA and DHA were superior to placebo in diminishing anger scores (3).
This is consistent with other studies including one that examined aggressive behaviours in an Australian prison population. They found that inmates with a lower Omega-3 Index were more aggressive and had higher attention deficit disorder scores (4) compared to those with higher indexes.
Interestingly, fish oils may have positive effects on mood and nicotine cravings. One study used exceptionally low daily doses (180 mg EPA and 120 mg DHA, or 300 mg combined) versus placebo for 3 months in a group of heavy smokers. At the end of the study, there was a greater reduction in levels of nicotine dependence, cigarette craving, and cigarettes smoked (5).
Another similar study used much higher doses of omega 3s (2710 mg EPA and 2040 mg DHA) for one month and the omega-3 treatment group experienced a significant decrease in reported daily smoking and tobacco cravings compared to the placebo group (6).
Omega-3 fats have been shown to have many different health benefits. More recently, their central role in brain and mental health is becoming increasingly better understood where mood disorders such as depression and anxiety are concerned, as well as maintaining cognition.
Considering this, it shouldn’t be much of a surprise to learn that they may have a role in the treatment and support of substance use disorders including protecting brain cells from substance use-related damage, reducing cerebral inflammation, and the all-important, management of cravings.