A Virus Infecting Gut Bacteria Intensifies Food Cravings

Gokushovirus—linked to serotonin and dopamine metabolism—was found in higher amounts in those who are obese and struggle with cravings.

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Some researchers suggest that a virus lurking in the guts of some people interferes with their neurotransmitters, giving them a larger surge of serotonin and dopamine (feel-good chemicals) when they eat junk food. In other words, they may be dealing with a microbial invader, making it more difficult to put down that family-sized bag of potato chips.

This newly revealed connection between the gut and the brain may explain one cause of food addiction, a controversial condition on which experts remain divided. The finding, published in Nature Metabolism, is based on animal models receiving human fecal transplants. More studies are needed, as the exact way the virus affects eating habits is unknown.

However, the discovery of the virus and its publicity could accelerate research into tests and treatments that may help curb America’s junk food crisis. Ultra-processed foods linked to chronic disease make up more than half of Americans’ daily calories. Many contain added sugar, synthetic additives, and other problematic ingredients.

Experts say the discovery could also be the epiphany patients need to propel lifestyle changes, such as cutting out ultra-processed foods or pursuing food addiction programs. Just as important is the potential shift in thinking the discovery might inspire doctors to consider food addiction more seriously.

Food Addiction Virus?

The study’s authors found the virus when they searched for specific gut microbes that might play a role in food addiction. They measured the microbiota and metabolites of three independent groups of people, and one candidate stood out: Microviridae bacteriophages. 

Bacteriophages, sometimes called phages, are viruses that attack bacteria (not human cells). The specific one at play in food addiction is called gokushovirus, according to Jordi Mayneris-Perxachs, lead researcher of the study.

Gokushovirus, a type of Microviridae phage, was also associated with higher body mass index and waist circumference, as well as high scores on the Yale Food Addiction Scale, a tool used mostly in research, which has found that higher scores are associated with obesity and binge eating.

Identify Food Addiction

While the scale hasn’t been adopted into formal diagnostic criteria, some clinicians and food addiction programs use it to assess whether eating processed foods is triggering an addictive response in some people. Among the traits of food addiction are:

• Lack of control over eating, leading to overeating
• A desire to quit eating the foods
• Repeated unsuccessful attempts to quit
• Distress caused by eating the foods
• Withdrawal symptoms, such as irritability, distractibility, and physical problems such as headaches

In a fourth group of nearly 1,000 people, researchers found the family of Microviridae phages was associated with a lack of self-control—a trait of food addiction. Additionally, these people had higher levels of tyrosine and tryptophan, amino acids that are precursors to dopamine and serotonin—neurotransmitters believed to play a role in addiction.

The National Institute on Drug Abuse describes the role of neurotransmitters as a sort of signal to the brain to repeat pleasurable activities. Because addictions create a larger surge in neurotransmitters, tolerance is achieved, and more of that drug is needed to activate the brain’s reward circuits.

However, as Mayneris-Perxachs told The Epoch Times in an email, the associations alone don’t prove whether Microviridae phages in the gut cause food addiction or are instead the consequence of food addiction.

What we do know from researchers, including Mayneris-Perxachs, is that a certain mix of microbes, including bacteria and viruses, is associated with food addiction. Gokushovirus may undermine beneficial bacteria that help us resist the effects of ultra-processed foods.

“We have shown these bacteriophages affect serotonin and dopamine metabolism, but we are not totally sure how,” he said. “Are they directly responsible, or are they influencing bacteria that then affect these neurotransmitters? These are some of the big questions we’re diving into next.”

Dig Deeper

The researchers performed tests on animals to determine causality. They transferred human gut microbiota—some containing gokushovirus and some without—to mice.

“Notably, mice that received microbiota from donors with presence of this virus developed behaviors consistent with food addiction, such as higher motivation to obtain chocolate pellets or difficulty in stopping reward-seeking behavior,” Mayneris-Perxachs said. “We performed a similar experiment but transferring only viruses, and we got the same results.”

Because the researchers had noted that anthranilic acid—a compound derived from tryptophan—was lower in people with high levels of gokushovirus, they decided to supplement the diets of mice with anthranilic acid to see if it might have a protective effect on food addiction behaviors. The results showed that those mice displayed more impulse control and were less interested in the chocolate pellets.

Could anthranilic acid become the next fad diet pill? If you are hoping a pill might help you not overeat junk food, be aware that it’s unclear what effect it would have on people. Also, it’s not widely available. That said, there are signs it may be helpful.

Anthranilic acid is a component of the anti-allergy drug tranilast, approved for asthma in Japan and South Korea. A study recently published in the Journal of Lipid Research showed that tranilast could be an effective off-label treatment for metabolic diseases such as nonalcoholic fatty liver disease, obesity, and Type 2 diabetes.

Leverage Phages

Researchers hope to be able to use phages to target bacteria linked to metabolic diseases, including the gut microbiome. The problem is that we know very little about these bacteria-killing viruses. About 90 percent of viruses in the microbiome remain unknown.

Just as certain viruses invade and frequently kill human cells, phages invade and kill bacteria. If those bacteria are harmful, we may experience a net benefit.

Clinical trials on phage therapy for gastrointestinal diseases are in the early stages. In one, a commercial cocktail of four phages was used to target pathogenic Escherichia coli (E. coli), which causes diarrhea. The cocktail was found safe and effective, reducing inflammation and bacterial burden.

“Phages should be considered as a promising therapeutic tool against pathogenic gastrointestinal bacteria,” according to a review in Microorganisms that noted that being able to identify a healthy phageome would offer a new approach to treatment.

The wider impact and possible side effects of such treatments remain largely unknown. For now, phage therapy is only clinically available in emergency scenarios under the U.S. Food and Drug Administration’s new drug rules.

To Medicalize or Not

Even with unknowns, this research could be relevant for patient care now, according to researcher-educator Nick Norwitz.

A Harvard Medical School student with a doctorate in metabolism, Norwitz shared the study results on his YouTube channel and Substack. It’s also the first of his videos that will be used in online medical school training.

“More and more people are appreciating food addiction is a phenomenon. It fits all the criteria of an addiction—or it can—and maybe more importantly, patient-clinician pairs are finding it useful to medicalize this,” he told The Epoch Times. “By appreciating that and acknowledging a food addiction, then people are actually empowered to address it.”

While there are pros and cons to medicalizing many conditions, Norwitz said the biological mechanism behind food addiction bolsters the case that it be taken seriously—even if there isn’t a treatment available for gokushovirus right now.

The findings remove some of the mystery behind a condition that’s largely believed to be a mental health flaw.

“I think this is incredibly empowering to patients. It doesn’t mean it has to be actionable in the moment,” Norwitz said. “There’s biology at play here, and as a biomedical community, it’s our responsibility to try to understand the biology to provide you with better solutions, even if we don’t have all of them right now.”

To Counsel Patients or Not

Should doctors compassionately explain to patients that there could be an underlying biological cause for their eating behavior? Doing so could be an improvement to what patients with food addiction typically encounter from doctors, according to Joan Ifland, founder of the Addiction Reset Community, who holds a doctorate in addictive nutrition.

Many struggling patients are traumatized by the medical system’s solutions, which range from being told they don’t have enough willpower to being ushered into surgeries that may help with weight loss but not food addiction, she told The Epoch Times.

A small study published in Nutrients found that dopamine release in response to a milkshake was the same before and after gastric surgery, illustrating that stomach-shrinking procedures may not necessarily shrink the desire to overeat highly palatable foods.

On top of the damage done by overeating processed foods, patients may stigmatize or isolate themselves.

“You’re working through a mountain of deceptive messaging,” Ifland said of patients. “It’s really important that people get that they are not failing, that they are not a loser. They are not incompetent. They aren’t stupid. They don’t lack willpower.”

Most everyone, Norwitz added, deals with something the medical system doesn’t have a solution for. That doesn’t have to mean doom and gloom for doctors or patients, he said. Rather, it should build compassion.

He believes people can be empowered—sometimes with medication—and sometimes by education. Doctors might consider bringing up the subject of food addiction with patients.

“That means we as a community of scientifically curious and health care providers can say: ‘Look, you’re struggling with something. And I’m sorry we don’t have the best solution for you right now, but we can give it a name and try to describe it.’”

However, it’s unusual for doctors to be up-to-date on all the latest research. Even with the speed of the internet, translational lag still impedes innovative patient care. Translational lag is the time it takes for research insight to translate into new clinical tools such as tests and treatments.

It’s simply impossible to keep up with newly released medical literature. Norwitz described it as like drinking water from a firehose.

“All the data puts an unfair expectation on doctors in light of what patients might actually know themselves through social media,” he said. “The unfortunate truth is that when there’s a headline ... your average clinician isn’t going to sit down and read the whole paper. Not because they’re lazy but because they’re working incredibly hard treating patients.”