Madona Azar, UMass Chan Medical School

Liver disease is frighteningly common worldwide.

Metabolic dysfunction-associated steatotic liver disease, or MASLD, is an umbrella term describing conditions related to a buildup of fat in the liver. Formerly known as nonalcoholic fatty liver disease, this condition affects 1 in 4 people worldwide. Among those with type 2 diabetes, insulin resistance, obesity or all three, the prevalence of MASLD increases to 3 in 4 people.

As a diabetologist, the possibility of liver disease is on my mind every time I see a patient. Understanding your risk of developing this common yet underrecognized condition is essential to treating it.

What is MASLD?

MASLD is a complex disorder with both environmental and genetic contributions. In its early stages, liver cells accumulate fat in a process called steatosis. Major sources of this fat include adipose tissue as well as fatty acids the liver makes in response to insulin resistance and excess caloric intake. This fat accumulation can enlarge the liver and interfere with its normal functioning.

Over time, fatty acids activate enzymes, which can produce toxic byproducts capable of causing liver cell injury, inflammation and scarring. This condition is better known as MASH, or metabolic dysfunction-associated steatohepatitis. Progression to MASH is more common in the presence of other risk factors such as type 2 diabetes, insulin resistance and metabolic syndrome.

Left unaddressed, MASLD and MASH can progress to liver scarring, failure and, in some cases, cancer. They also increase risk of death from cardiovascular disease and liver-related complications.

In the U.S., MASH is the leading cause of liver transplants due to hepatic cancer among women and in those 65 and older. It is also on track to overtake hepatitis B and C as the main reason people develop liver cancer and thus need a liver transplant.

Liver disease and type 2 diabetes

Three out of four people with type 2 diabetes have MASLD. Linking liver disease, type 2 diabetes and obesity is the key role insulin resistance plays in their genesis.

Obesity is associated with increased fat deposits around the internal organs and higher levels of fatty acids delivered to the liver. Accumulation of fat in the liver increases its resistance to insulin.

Normally, insulin suppresses glucose production in the liver when blood sugar is high. When the liver becomes resistant to insulin, it produces more glucose despite elevated blood sugar levels, which in turn contributes to the development of type 2 diabetes.

A 2015 meta-analysis found that people with MASLD have a nearly twofold greater risk of developing type 2 diabetes than those without the disease. MASLD is also more likely to progress to MASH in the presence of type 2 diabetes.

MASLD disproportionately affects certain ethnic groups. For instance, 1 in 5 people of Hispanic descent in the U.S. have MASLD, with or without diabetes. This is thought to be related to genetic mutations that affect how the liver cells process fat. One particular mutation more common in Hispanic people promotes steatosis by interfering with the cells' ability to clear fat deposits.

Treating MASLD and MASH

The silver lining is that management of obesity and type 2 diabetes – such as through lifestyle changes – is very similar to management of MASLD. The most critical early interventions for type 2 diabetes can also help with MASLD, and this is not surprising given how closely interrelated these two conditions are.

The best way to reverse the early stages of MASLD is with weight loss through healthy eating habits and regular exercise. The aim is to shed at least 5% to 10% of initial body weight, maintain that weight loss through sustainable and realistic lifestyle choices, and avoid excess alcohol intake to limit additional liver injury.

New medications to treat diabetes, such as GLP-1 receptor agonists like Ozempic and Mounjaro, as well as SGLT2 inhibitors like Jardiance or Invokana, have also shown benefit in early stages of MASLD. These drugs promote weight loss, which in turn improves MASLD. In addition, studies have shown that Ozempic and Mounjaro could reverse MASH, even with inflammation and fibrosis.

Older medications used for diabetes, such as pioglitazone, typically can also help reduce the progression of MASH by reducing insulin resistance.

In people with severe obesity or who have not had success with lifestyle changes and weight loss drugs, bariatric surgery is another highly effective option to treat MASLD, as it is associated with significant and sustained weight loss.

New drugs are also in the pipeline. The Food and Drug Administration recently approved a new medication called resmetirom to treat MASH with advanced liver scarring.

However, a cure for this chronic disease remains elusive. This is why it is essential to diagnose MASLD as early as possible and use proven measures that can be maintained long term. Treatments and lifestyle changes need to be deployed as early as possible, before inflammation and scarring have firmly set in. MASH gets trickier to treat in more advanced stages when liver damage becomes irreversible. For instance, while Ozempic may help treat early MASH, it doesn't benefit patients with more advanced stages of liver scarring.

Ignorance is not bliss

Very few people are aware of MASLD and its health implications, including those living with it. While roughly over 35% of U.S. adults have MASLD, less than 5% are aware they have liver disease.

MASH can be difficult to diagnose because it either causes no symptoms or can be mistaken for other conditions. Patients may have the condition for years and not be aware that it is slowly and meticulously causing damage. In that sense, MASH is strikingly similar to type 2 diabetes or high cholesterol.

Young people are increasingly being diagnosed with early-onset MASLD. Indeed, MASLD with MASH is the most common pediatric liver condition, affecting nearly 8% of children and adolescents and over 34% of children with obesity in the U.S. These children and adolescents are at high risk of developing type 2 diabetes and have a significantly increased lifetime risk of cardiovascular disease and cancer.

Health care costs for people with type 2 diabetes and MASH are estimated to reach US$55 billion over the next 20 years, accounting for 65,000 liver transplants, 1.37 million cardiovascular-related deaths and 812,000 liver-related deaths.

These grim statistics need not be if MASH is tackled early and aggressively.

If you are one of the millions of Americans with prediabetes or diabetes and are also overweight, you most likely have some degree of MASLD or MASH. Being aware of MASLD and getting checked is the first step to addressing it.

Promptly determining the best way to treat your MASLD or MASH is the next step. An early referral to a liver specialist will help you halt the progression of this challenging and common condition and take advantage of the treatment breakthroughs researchers have made in the past few years.

Madona Azar, Associate Professor of Medicine, UMass Chan Medical School

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Samantha Scarneo-Miller, West Virginia University

High school sports teams start practices soon in what has been an extremely hot summer in much of the country. Now, before they hit the field, is the time for athletes to start slowly and safely building up strength and stamina.

Studies have found that the greatest risk of heat illness occurs in the first two weeks of team practices, while players' bodies are still getting used to the physical exertion and the heat. Being physically ready to start increasingly intense team practices can help reduce the risk.

I am an athletic trainer who specializes in catastrophic injuries and heat illnesses. Here's what everyone needs to know to help keep athletes safe in the heat.

Why should athletes restart workouts slowly?

One of the biggest risk factors for developing dangerous exertional heat illnesses is your physical fitness level. That's because how fit you are affects your heart rate and breathing, and also your ability to regulate your body temperature.

If an athlete waits until the first day of practice to start exercising, their heart won't be able to pump blood and oxygen through the body as effectively, and the body won't be as adept at dissipating heat. As a person works out more, their body undergoes changes that improve their thermoregulation.

That's why it's important for athletes to gradually and safely ramp up their activity, ideally starting at least three weeks before team practices begin.

There is no hard and fast rule for how much activity is right for preparing – it varies by the person and the sport.

It's important to remember not to push yourself too hard. Acclimatizing to working out in the heat takes time, so start slow and pay close attention to how your body responds.

How hot is too hot for working out outside?

Anything that is hotter than normal conditions can be risky, but it varies around the country. A hot day in Maine might be a cool day in Alabama.

If it's significantly hotter outside than you're used to, you're more likely to get a heat illness.

To stay safe, avoid exercising outside in the hottest periods. Work out in the shade, or in the early mornings or evenings when the sun's rays aren't as hot. Wear loose clothing and light colors to dissipate and reflect as much heat as you can.

Hydration is also important, both drinking water and replenishing electrolytes lost through sweating. If your urine is light-colored, you are likely hydrated. Darker urine is a sign of dehydration.

What does acclimatization look like for teams?

Once team practices start, many states require heat acclimatization processes that gradually phase in activity, though their rules vary. Some states require 14 days of heat acclimatization. Some require six days or none. Some only require it for football.

Athletes who get a head start on acclimatization can help their bodies adapt faster and more efficiently to the heat. Regardless of what your state requires, all athletes participating in all sports should acclimatize carefully.

Heat acclimatization involves adding more strain during the workout every few days, but taking care not to add too much.

For example, instead of starting the first day of practice with full pads and full contact in football, players might start with just the helmets for the first few days.

Acclimatization is also about limits: Holding practice only once a day in the beginning and capping how many hours players practice each day can help avoid putting too much strain on their bodies too fast. Coaches and athletic trainers must also keep an eye on the wet bulb global temperature – the combination of heat, humidity, radiation and wind speed – to gauge the heat risk to players and know when to limit or cancel practice.

This isn't just for football. Whether it's soccer, track and field, softball or baseball, heat illnesses do not discriminate. A Georgia basketball player died after collapsing during an outdoor workout in 2019 – she was accustomed to practicing indoors, not in the heat.

What are warning signs an athlete is overheating?

If a player starts to slow down or gets lethargic, that may be a sign that they're overheating. You might see evidence of central nervous system problems, such as confusion, irritability and being disoriented. You might see someone stumbling or trying to hold themselves up.

Most of the time, someone with exertional heatstroke will be sweating. They might have red skin and be sweating profusely. Sometimes a person with heat stress can lose consciousness, but most of the time they don't.

What should you do if someone appears to have a heat illness?

If someone appears to be suffering from heat illness, cool them down as fast as possible. Find a tub you can put the person in with water and ice. Keep their head out of the water, but cool them as fast as possible.

Immersion in a cool tub is best. If you can't find a tub, put them in a shower and put ice around them. Even a tarp can work – athletic trainers call it the taco method: Put the patient in the middle of the tarp, put some water in with ice, and hold up the sides to oscillate them slowly so you're moving the water from side to side.

Every sports team should have access to a cooling vessel. About half the states require it. As that expands, these safety practices will likely trickle down to youth sports, too.

If a player appears to be suffering from heatstroke, cool them down and call 911. Having a comprehensive emergency action plan ensures that all personnel know how to respond.

What else can teams do to prepare?

Exertional heatstroke is a top cause of sports-related death across all levels of sports, but proper recognition and care can save lives.

Athletic trainers are vital for sports programs because they are specifically trained to recognize and manage patients suffering from exertional heatstroke and other injuries. As hot days become more common, I believe all sports programs, including high school sports programs, should have an athletic trainer on staff to keep players safe.

Samantha Scarneo-Miller, Assistance Professor of Athletic Training, West Virginia University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Rachel Mallinger, University of Florida

Many plants, from crops to carnations, cannot bear fruit or reproduce without bees, beetles, butterflies and other insects to pollinate them. But the population of insect pollinators is dropping in the U.S., due in part to pesticides, climate change, invasive plants and diminished habitats. Rachel Mallinger, assistant professor of entomology at the University of Florida, explains why these insects are in decline and how homeowners can create yards and gardens that are good for pollinators.

The Conversation has collaborated with SciLine to bring you highlights from the discussion that have been edited for brevity and clarity.

What kind of insects pollinate?

Rachel Mallinger: A lot of different insects pollinate. Insects visit flowers for many purposes, often for food, to get nectar or to get pollen. Sometimes they'll visit flowers to mate or to lay eggs or as refuge. Bees are the primary pollinators for a lot of plants, but flies, wasps, beetles and butterflies also play an important role.

How ecologically critical are insect pollinators?

Mallinger: A small percentage of flowering plants are pollinated primarily by wind, but new research suggests that as much as 90% require animal pollinators. Although birds, bats and other mammals also pollinate, insects are the main pollinators for the vast majority of those plants.

Without insects and their pollination, these plants would not be able to reproduce, and we would see a dramatic decline in plant diversity and abundance. Without insect pollinators, these plants wouldn't produce the seeds and the fruit that feed many animals – including people.

Have insect pollinator populations declined?

Mallinger: Recent studies have shown pretty dramatic declines in insects generally, and this has been shown even in conservation lands. So we think that in highly developed areas, insect declines are probably even more dramatic.

I study primarily native wild bees. Here in North America, we have between 4,000 and 5,000 species. For many species, we don't know if they're declining. Of the ones that we do have some information on, it's estimated that about half are declining and about a quarter are imperiled and potentially on the road to going extinct.

The insect pollinators that tend to be most at risk are ones that are specialists – those that require really unique, specialized food or nesting resources. Also ones that already have a limited range. For example, maybe they are found only on islands or in a small area.

What about the economic importance of insect pollinators?

Mallinger: Crops pollinated by animals, primarily insects, make up about one-third of our agricultural production in terms of acreage. A study in the state of Georgia found over US$360 million per year in crop pollination services provided by insects in that state alone.

What do insect pollinators need to be healthy?

Mallinger: Aside from pollen and nectar, some insect pollinators require additional food sources. For example, butterflies in the caterpillar stage need foliage from their host plants.

Other insect pollinators, like wasps and flies, are carnivores in the larval stage, so during that time they need to eat small arthropods – like spiders and centipedes – and insects.

Beyond that, they need nesting habitat. The majority of our insect pollinators nest below ground, and so they need ground that is relatively undisturbed, bare and accessible. Other pollinators nest in woody debris, stems and reeds. And some pollinators, like butterflies, just lay their eggs on host plants.

Additionally, pollinators need environments that are free from toxins. So they need environments that are not regularly sprayed with pesticides, including insecticides.

What stressors are leading to declines in insect pollinator populations?

Mallinger: I would say there are five main stressors.

Land use change is one. This can be the conversion of wild lands to agriculture or to development.

Climate change is another stressor. It changes the average temperature that these pollinators are experiencing and increases the chance of extreme temperatures and weather events. Hurricanes and flooding can be really detrimental and destroy the habitat for pollinators.

Third, pesticides and other chemicals in our environment that are toxic.

Invasive plants can be really detrimental for pollinators. They can take over an area and replace the native plants that pollinators depend on. That's four.

And finally, pathogens and parasites.

All five of these stressors can interact. For example, climate change may increase the likelihood of invasive plant species, pathogens and parasites thriving. Land use change can also increase the likelihood of invasive species.

What can homeowners do to help pollinators?

Mallinger: Planting a diversity of flowering plants for pollinators is one of the best things you can do. Aim to have at least three plants flowering at any given time, and look for a diversity of flower colors and shapes. Different pollinators have different preferences. You can have flowers that are yellow, blue, purple, pink, red and white.

In terms of floral shapes, plant some flowers that are flat and are accessible for pollinators with small mouthparts. And also plant some flowers with medium-length tubes, and some with long tubes.

Focus on native plants and try to seek out plants that might not just be the common types that you find in the big box stores. Go to native plant nurseries and seek out resources online.

Additionally, try to have nesting habitat in your garden. If the space allows, have some woody debris around for the pollinators that nest above ground. This can include things like logs, stems and reeds. Also manage your area to be as chemical-free as possible. This includes reducing pesticide use.

Keep in mind that many pollinators that nest below ground are not aggressive and are solitary. It's just one individual pollinator and her nest.

Watch the full interview to hear more.

SciLine is a free service based at the American Association for the Advancement of Science, a nonprofit that helps journalists include scientific evidence and experts in their news stories.

Rachel Mallinger, Professor of Entomology, University of Florida

This article is republished from The Conversation under a Creative Commons license. Read the original article.