Metabolic dysfunction-associated steatohepatitis (MASH) is a form of fatty liver disease that promotes inflammation and damage over time. Closely connected to conditions like obesity and insulin resistance, MASH affects nearly one-third of people worldwide. A recent study found that a long-term intervention combining calorie restriction and high-intensity interval training (HIIT) in people with MASH improved liver function, doubling insulin sensitivity.
Researchers assigned people with MASH to either a treatment group (16 participants) that received lifestyle counseling and exercise training or a control group (eight participants) that continued with standard medical care. The treatment group engaged in supervised HIIT three times a week while reducing caloric intake. The researchers assessed the participants' liver fat, measured blood biochemistries, and evaluated insulin sensitivity before and after the intervention.
They found that the treatment group experienced notable reductions in body weight, fat mass, and liver injury. Their cardiorespiratory fitness improved considerably, and they exhibited a twofold increase in peripheral insulin sensitivity compared to the control group. Both groups saw reductions in total energy intake and liver fat.
These findings suggest that combining caloric restriction with regular high-intensity exercise can yield marked improvements in liver health and insulin sensitivity, likely by redistributing excess nutrients to skeletal muscle. Learn more about calorie restriction in this clip featuring Dr. David Sinclair, and HIIT in this clip featuring Dr. Martin Gibala.
Depression is a major public health concern, affecting more than 322 million people worldwide. A hallmark of depression involves reduced activity in specific brain areas and heightened activity in others, impairing brain connectivity. A recent study found that repetitive transcranial magnetic stimulation (TMS)—a non-invasive procedure that uses magnetic fields to stimulate nerve cells in the brain—improved brain connectivity in people with treatment-resistant depression.
The study involved 75 participants with treatment-resistant depression who underwent 20 treatment sessions over five consecutive days. Researchers randomly assigned them to three groups: a dual-target group receiving TMS to both sides of the brain, a single-target group, and a control group that received a sham treatment. Each session lasted 22 minutes, with functional magnetic resonance imaging conducted before and after treatment to assess changes in brain activity.
They found that 47.8% of patients in the dual-target group responded favorably to treatment, compared to 18.2% in the single-target group and just 4.3% in the sham group. The active treatment demonstrated greater effectiveness at the four-week follow-up than the sham. Notably, many participants exhibited low baseline brain connectivity, and higher connectivity predicted better outcomes.
These findings suggest that dual-target TMS promotes rapid and clinically significant improvements for people with treatment-resistant depression. Lifestyle behaviors, including sauna use and exercise, can help people with treatment-resistant depression, too. Learn more about the role of lifestyle in managing depression in our overview article.
Body art is more popular than ever, with roughly one-third of people in the U.S. having at least one tattoo. However, tattoo inks often contain harmful chemicals, including carcinogenic pigments and metals. A recent study found that people with tattoos are 21% more likely to develop malignant lymphoma.
Researchers conducted a case-control study among roughly 1,400 people diagnosed with malignant lymphoma (“cases”) in people aged 20 to 60 over 10 years. They matched the cases with age- and sex-matched people without cancer (“controls”) from the general population. Then, they gathered information about the participants' tattoo exposure and assessed the relationship between tattoos and lymphoma risk.
They found that overall, participants with tattoos were 21% more likely to develop malignant lymphoma than those without. The risk of lymphoma among those who had received their first tattoo within the previous two years was 81% higher than those without a tattoo. Risk decreased nearly to baseline between three and 10 years after the first tattoo but increased again to 19% after 11 years, suggesting that long-term exposure to tattoo-related chemicals contributes to a delayed but persistent risk of developing lymphoma.
Undergoing laser removal of tattoos increased the risk of lymphoma by 163%. Oddly, greater tattoo surface area did not increase risk, with the highest lymphoma risk among people with tattoos smaller than the size of a deck of cards.
These findings point to potential links between tattoos and an increased risk of lymphoma. The tattooing process involves injecting ink into the skin through repeated punctures, breaching the skin’s protective barrier and triggering an immune response. As the ink enters the body, immune cells called macrophages attempt to engulf and isolate the foreign substance, driving the movement of pigment to nearby lymph nodes. Lasering tattoo ink induces the formation of toxic, carcinogenic substances that can persist in the body.