Diabetes Joint Pain: Symptoms and Treatment

Inflammation Isn't Always Bad. Here's How We Can Use It To Heal.

As an athletic teenager in Ireland, Joseph Costello often followed hard training sessions with ice baths. By the time he was a graduate student, he had found a more extreme method to chill the sore muscles and joints that come with exercise-induced inflammation: standing in a chamber cooled to -110° Celsius (-166° Fahrenheit) for a few minutes at a time.

The experience was equal parts excruciating and invigorating, says Costello, who started researching this kind of cold exposure, called cryotherapy, for his PhD, which he finished in 2012. "It was literally out of this world," says Costello, an exercise and environmental physiologist at the University of Portsmouth in the U.K., who used to play Gaelic football and other sports. "The coldest temperature ever recorded on Earth was about 20 degrees Celsius warmer than this."

Over a decade later, ice plunges and cold showers are trendier than ever as strategies for battling inflammation, and it's not the only approach people are taking to hack their own health. Also popular: heat exposure, alternating heat and cold, and injections that require assistance from a healthcare provider.

(This is what a cold plunge does to your body.)

Members of a cold water dipping group dip into Vermont's icy Lake Champlain to promote good physical and mental health. 

Photograph by Amy Toensing, National Geographic Image Collection

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But do any of these inflammation-hacking techniques help accelerate healing? Evidence is both promising and murky, with some studies showing benefits, some showing no effects, and others showing that inflammation-control tactics can backfire in some cases. As scientists investigate, they are unraveling an enduring mystery: When is inflammation good and when does it cause harm?

"Inflammation gets a bad rap—everybody's trying to decrease inflammation in their body," says Dean Wang, an orthopedic surgeon and chief of the sports medicine division at the University of California, Irvine. "But not all inflammation is the same, and controlled inflammation is necessary for healing. I don't think people understand that enough."

Inflammation to the rescue

Painful joints are a near-universal experience. Osteoarthritis affects an estimated 80 percent of people over 55. Many more develop injuries, which become increasingly common—and slower to heal—with age. Inflammation is a major driver of musculoskeletal pain that comes with both injuries and arthritis, studies suggest. But controlling the discomfort is a tricky problem, in part because inflammation is an essential process that our bodies have developed to repair damage.

Here's how it works. When someone strains or tears a ligament or tendon, the insult triggers the release of inflammatory molecules and cytokines, starting a sequence of events known as acute inflammation. Immediately, blood vessels dilate to allow more fluid to flow into the injured area. Swelling and clotting ensue while yet more inflammatory cells arrive to clear out damage and mobilize still other cells to rebuild damaged tendons, ligaments, and other tissues.

In this magnified view of a skin wound, red blood cells (right) become trapped in a mesh of protein fiber, forming a clot that helps prevent blood loss. Photograph by Steve Gschmeissner, Science Source

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This acute inflammatory process is so integral to healing, Wang says, that during many shoulder and knee surgeries, he uses a sharp tool to scrape the tissue he's working on to "muck it up a bit" and cause bleeding. That accelerates the inflammatory pathways that do the work of repair, even in cases of chronic pain and inflammation that continue longer than the acute phase.

Shots for inflammation control

The idea of tinkering with inflammation underlies an increasingly popular medical approach, called platelet-rich plasma or PRP, aimed at treating more chronic types of pain from tendonitis, arthritis, and other problems. Injections of PRP are made from a person's own blood, which is first spun rapidly to filter out red blood cells and isolate platelets, which are essential for clotting and full of anti-inflammatory growth factors.

Mixed back together, PRP shots can contain various concentrations of white blood cells and other ingredients that dial inflammation up or down as needed, Wang says. For his arthritis patients, he uses an anti-inflammatory PRP. For people with chronic tendon injuries, like tennis elbow or hamstring strains, he makes pro-inflammatory formulations.

Shots of platelet-rich plasma, or PRP, are used to treat chronic pain from physical injuries and encourage skin rejuvenation.

Photograph by Евгений Вершинин, Alamy Stock Photo

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Efforts to evaluate the effectiveness of PRP remain a work in progress, in part because it is being used in many different ways. In a 2021 review, Wang and colleagues reviewed 132 studies on the use of PRP for 28 conditions in eight specialties, including musculoskeletal issues, cosmetic uses, and neurology. Overall, 61 percent of the studies supported the use of PRP, though only a third detailed the PRP formulation used. Also, studies varied in how they measured outcomes, making them hard to compare with each other.

"The practice of it is far outpacing the science," Wang says. "But our science is good enough to show that there's some promise with these treatments. For mild to moderate degeneration or knee arthritis, these things are worth trying if you've tried some other things and they don't work."

Injections of the future may include adult stem cells (which regenerate damaged tissue) and the proteins they produce (called secretomes). These shots are also widely available, Wang says, but research is still ongoing, and it's not yet clear if positive outcomes result from biological processes or placebo effects.

Inflammation on ice

For people who want to take inflammation into their own hands without needles, cold exposure has become a leading contender, with ice plunges selling for thousands of dollars and attracting devotees who rave about their ability to ward off pain, anxiety, depression, and more. People who embrace the chill often invoke inflammation as the link between cold exposure and health benefits.

Scientists are still working on making that direct connection. Studies show that cold helps with pain, probably by lowering skin temperature, which reduces the speed that nerves can deliver pain messages, Costello says. The intensity of extreme cold exposure may also work as a distraction from what hurts. But studies that have tried to assess the effects of cold exposure on both acute and chronic inflammation have produced conflicting results.

After an injury, infusions of cold saline reduce inflammation in animals, studies show. And in a 2013 study that included 20 men who ran downhill for 40 minutes at a -10 percent grade, there was a slight reduction in inflammatory molecules among the half of participants who sat in a 40°F ice bath for 20 minutes afterwards. But those results weren't statistically significant, and the ice bath made no difference in muscle soreness. For a different study, researchers took muscle biopsies from nine young men who did a strength workout followed by a 10-minute cold plunge in 50°F water. They found no difference in the inflammatory response compared with a post-exercise light spin on an exercise bike.

Cold therapy may also counteract the muscle gains that come with exercise, studies show, possibly by interfering with the inflammatory process. In some cases, cold interventions might even increase inflammation, Costello says.

"There's more evidence coming out on an annual basis," he says. "But there are still only a handful of research studies that are supporting the effectiveness of cold therapy for reducing the inflammatory response."

Playing with fire

Heat might be another way to address inflammation and improve health. Regular sauna users have a lower risk of cardiovascular disease, according to research on men in Finland. And a type of physician-supervised procedure that raises body temperature has shown promise for treating depression and cancer.

Heat, including soaking in hot water like this spring in China, may also lower the risk of inflammation and heart disease. 

Photograph by Michael S. Yamashita, National Geographic Image Collection

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In a 2021 review of research on repeated sauna and hot-tub use, University of Oregon environmental physiologist Chris Minson and colleagues found evidence of multiple ways that heat can suppress pro-inflammatory pathways and enhance anti-inflammatory ones in animals and people.

In heart failure patients, two weeks of bathing in hot springs led to a drop in multiple inflammatory molecules. And 30 one-hour sessions of hot tubbing over 10 weeks reduced levels of a main measure of inflammation, called C-reactive protein, in the blood of women with polycystic ovary syndrome, Minson's group reported in 2019.

People vary quite a bit in their inflammatory levels, which can also change in a single person from day to day and even throughout the day, experts say, making it tricky to give evidence-based advice that applies to everyone. Costello advises against icing after every workout because it could interfere with healing and athletic gains.

On the other hand, cold might help with pain that makes it hard to move or interferes with daily activities, or when chronic low-level inflammation sets in and inhibits the normal repair process, Minson says. He recommends separating cold exposure from exercise by, for example, plunging first thing in the morning and exercising later in the afternoon.

Exercise itself has powerful anti-inflammatory effects, Minson adds. Taking anti-inflammatory medications or other measures that impede the inflammatory process can interfere with those benefits, at least in healthy young people. "Inflammation is super important for the healing process," Minson says. "By knocking it back, it's not necessarily a healthy thing."

Back to nature

If hot tubs and cold plunges feel good, the experience may have benefits beyond inflammation that, in fact, ultimately affect it. People who swear by cold plunges often report a sense of euphoria, like they've woken up, feel more alive and less stressed, Minson says. One soak in 55°F seawater for up to 20 minutes led to a large drop in negative thinking and a major boost in mood for 42 undergraduate students who soaked for a 2021 study.

That sense of well-being could have important physiological benefits. Studies of cold plunging, which tend to be small, have shown reductions in the stress hormone cortisol. When chronically elevated, cortisol can lead to persistent low-level inflammation.

Cold plunges in natural settings might be especially beneficial, adds Minson, who is also chief science officer of a free app called NatureDose that aims to get people outside more. Spending time in nature, according to many studies, improves physical and mental health.

Hiking can be healthy but too much can inflame tired joints. Scientists are working on ways to treat arthritis and sports injuries to help us keep on moving.

Photograph by Mark Stone, National Geographic Image Collection

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The routines and community that habitual cold-water swimmers and sauna bathers often develop have yet more benefits for the immune system, says Costello. To reap benefits safely, he advises people to check with a medical professional before exposing themselves to extreme temperatures.

Minson recently put a sauna in his backyard next to a small workout space. Most days, he spends about half an hour in the hot room, punctuated by a cold shower. His research has convinced him that the practice is good for him. More than that, he is motivated by how good it makes him feel. "When I take care of my body by doing these kinds of things, I sleep better," he says. "I'm happier. I feel healthier."

Role Of 'hunger Hormone' Receptor In Obesity-realted Chronic Inflammation

Texas A&M AgriLife Research study may lead to novel obesity treatment New study provides insights on role of 'hunger hormone' receptor in obesity-realted chronic inflammation

A team comprised primarily of Texas A&M AgriLife Research scientists has made an important discovery that could lead to a novel treatment for obesity and obesity-associated diseases or conditions.

Details of the discovery can be found in the study "Nutrient-sensing growth hormone secretagogue receptor in macrophage programming and meta-inflammation," published in the January issue of Molecular Metabolism.

Yuxiang Sun, Ph.D., is the lead investigator on a study that could lead to a novel treatment for obesity and obesity-associated diseases or conditions. (Texas A&M AgriLife photo by Michael Miller)

"Chronic inflammation commonly associated with obesity is a key reason obese individuals often have many other chronic diseases," said Yuxiang Sun, Ph.D., professor and AgriLife Research Faculty Fellow in the Texas A&M College of Agriculture and Life Sciences Department of Nutrition and associate member of the Texas A&M Institute for Advancing Health Through Agriculture, IHA.

Sun, who served as lead investigator for the study, was among several investigators from the Department of Nutrition. Study contributions were also made by other entities in The Texas A&M University System.

Competitive funding for the study came from the National Institutes of Health. It was also supported by the IHA -- the world's first research institute to bring together precision nutrition, responsive agriculture and behavioral research to reduce diet-related chronic diseases.

About the study

The study focused on the role of one molecule involved in how our bodies deal with hunger: the growth hormone secretagogue receptor, GHSR, which mediates the effect of ghrelin, known as the "hunger hormone." Studies have shown that ghrelin promotes eating and increases fat. Ghrelin activates GHSR to increase appetite, fat accumulation and insulin resistance.

Research has shown that under normal conditions, GHSR is highly active in the brain but much less active in other tissues such as liver and fat, also referred to as adipose tissue. For this reason, most ghrelin research has focused on the brain.

"Intriguingly, in previous research, we found the complete removal of GHSR protects against diet-induced inflammation and insulin resistance in adipose tissue and the liver without affecting food intake," Sun said. "This was very puzzling because that GHSR has very low expression in fat and liver cells."

A link between obesity and the immune system

Sun and her team has made the novel observation that GHSR activity in macrophages -- a major immune cell type in tissues -- increases dramatically under the condition of obesity. In this study, Sun's team investigated whether ghrelin's effect in adipose tissues and the liver was due to the infiltration of GHSR-expressing macrophages into these tissues under the condition of obesity.

"If that was the case, this infiltration by those particular GHSR-expressing macrophages would trigger chronic inflammation and insulin resistance," Sun said.

Study results and implications

To understand the role of GHSR in macrophages, the team developed a unique animal model to selectively shut down GHSR activity in macrophages.

"Indeed, our study results showed that macrophage-specific GHSR deficiency reduces diet-induced systemic inflammation and insulin resistance," Sun said. "Remarkably, GHSR deficiency in macrophages reduced diet-induced macrophage infiltration, macrophage activation and fat deposition in adipose tissue and the liver."

In addition to their effect on diet-induced chronic inflammation, the study also demonstrated that GHSR-deficient macrophages protect against acute inflammation induced by bacterial toxins.

At a molecular level, they found GHSR programs macrophages through an insulin signaling pathway, Sun said. Basically, this study showed that macrophage GHSR controls chronic inflammation in obesity by regulating macrophage programming.

She said the study's novel results demonstrate that macrophage GHSR plays a key role in meta-inflammation by promoting macrophage infiltration and inflammatory activation.

"These exciting new findings helped to resolve a long-time mystery of GHSR in adipose tissue and the liver in obesity, by uncovering the novel immunoregulatory role of GHSR and revealing that GHSR signaling is a critical link between metabolism and immunity," Sun said.

She said the study adds a new dimension to the biology of ghrelin, and underscores that ghrelin is not only a hunger hormone, but also an important nutrient-sensor and immune regulator.

"This has profound implications for health and disease, as blocking GHSR in macrophages may serve as a promising immune therapy to prevent or treat obesity, diabetes and inflammation," Sun said.

Dr Libby: What You Can Do Daily To Lower (And Prevent) Inflammation

These simple changes may reduce low-grade inflammation.

At its heart, inflammation is our body's innate crusader, springing into action at the first sign of injury or infection.

Picture it as a well-oiled machine, deploying an army of cells and messengers to heal and protect. Yet when this balance tips, our protector becomes the perpetrator, potentially leading us down a path of chronic illness and diminished vitality.

The persistent and often silent nature of chronic inflammation can contribute to a wide range of health challenges, often with long-term implications, including a higher risk for developing cardiovascular disease, myriad cancers, type 2 diabetes, joint conditions, Alzheimer's disease and inflammatory bowel diseases, to name a few.

The good news is, inflammation that goes beyond the bounds of helpful is very much influenced by diet and lifestyle. Let that empower you.

How does your diet impact inflammation?

Eating in a way that focuses on food (whole real food) and minimises junk (most processed foods) can be a fantastic step towards lowering inflammation in the body. Think of it as eating in a species-specific way.

There are also a number of foods that have potent anti-inflammatory properties and increasing our consumption of these can help too. These include turmeric, ginger, flaxseeds, and oily fish, due to their long-chain omega-3 fatty acid content, as well as grass-fed meats.

Some may benefit from supplementing with curcumin (the main active constituent in turmeric) or a high-quality fish oil to help with lowering inflammation, however, this is best discussed with your qualified healthcare practitioner first to determine if it is suitable for you. For most people, it is.

Not only does eating predominantly whole real foods go a long way to ensuring we are getting as much nourishment from what we put in our mouth as possible, but it also plays a powerful role in the composition of our gut microbiome.

Emerging research suggests that a problematic gut microbiome — disrupted by factors like antibiotics, the constant relentless production of stress hormones and poor diet — can trigger chronic low-grade inflammation while some types of gut bacteria can decrease inflammation.

Consuming a diverse range of vegetables as well as fibre-rich foods and fermented foods can nurture a healthy gut ecosystem and foster a more harmonious relationship with our immune system. Variety is key — think different types of vegetables, fruits, nuts, seeds, pulses, herbs and spices along with fermented foods such as sauerkraut, miso, kombucha, kimchi, tempeh and kefir.

How you eat is just as important as what you eat. Ensure you chew your food well, eat slowly in a calm undistracted state.

What's your liver got to do with it?

The liver is responsible for detoxifying (altering the structure of) problematic substances inside us so that they can be eliminated.

When the liver isn't able to do this critical detoxification work efficiently, which might be due to factors like damage from long-term alcohol consumption, pollutants or viruses, inflammation increases.

Reducing our exposure to what I like to call "liver loaders" — alcohol, refined sugars and synthetic substances that are often found in ultra-processed foods and drinks, conventional cosmetics and household cleaning products — makes an enormous difference.

Will reducing stress reduce inflammation?

Our lifestyle is so much more than what we put or don't put on our plate.

Stress plays a significant role in chronic inflammation. When adrenaline (one of our stress hormones) is consistently elevated day after day, it can trigger the release of inflammatory chemicals that can act unfavourably on all sorts of things, including the lining of our blood vessels.

This is a key reason why stress has been linked to an increased risk of cardiovascular diseases and metabolic disorders. Incorporating stress-management techniques like meditation, yoga or slow breathing exercises can effectively help to curb stress-induced inflammation — research shows this over and over again.

Often, we need to also explore our perceptions of pressure and urgency, as the way we think and feel plays a significant role in whether our body perceives aspects of our life as a source of stress or not.

Why it's important to exercise

It's important to remember, too, that our bodies are not designed for the sedentary lifestyle many now lead. We are made to move, and to move with regularity throughout the day.

A mostly inactive lifestyle can exacerbate inflammation. Some physical activity acts as an anti-inflammatory agent. It enhances blood flow, stimulates the release of endorphins and reduces the production of inflammatory markers. Engaging in regular movement and exercise can have a profound impact on reducing systemic inflammation and promoting overall wellbeing.

There is also a growing body of emerging evidence supporting the use of cold water immersion therapy or ice baths for a variety of health conditions — including reducing inflammation. This practice involves immersing the body in cold water or alternating between warm and cold water, for short periods of time, usually between five and 20 minutes. This is something you can do in the ocean (when the weather is cold enough), your shower or at a local recovery centre or bathing house.

Other environmental factors

Beyond lifestyle choices, environmental factors also contribute to inflammation.

Air pollution, for instance, is often invisible yet can initiate an inflammatory response in the airways or lungs.

Exposure to problematic levels of substances such as heavy metals, pesticides and industrial chemicals, can trigger chronic inflammation and damage cellular structures.

Minimising exposure to these harmful substances through what we consume, apply to our skin and use in our household can help reduce the burden of inflammation on our body as well as in the environment.

Do what you can and then see if you can stretch a little further.

Dr Libby Weaver PhD is a nutritional biochemist, 13 times best-selling author and international keynote speaker. Her Detox by Dr Libby course, starting February 5, is a 28-day programme designed to help you decrease your total body burden. Drlibby.Com

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