a primer on joint health
We’re active guys. We push ourselves to the limit. We chase excellence, and we strive for greatness. Our endeavors require a sharp, focused mind, and we expect peak physical performance from our bodies as well. This article is all about how you can use supernutrients from whole foods and certain supplements to make sure that you keep moving effectively, efficiently, and comfortably for the long haul.
You’re Not Getting Any Younger
Joint discomfort and stiffness impair mobility, adversely affect daily activities, and negatively impact quality of life.1,2 Simply put, tired, worn, and stiff joints can limit you from doing what you love to do and living the life of your dreams. Research shows that 43% of folks between the ages of 45 – 65 years old struggle with joint discomfort.3 Beyond that, it is estimated that 80% of the population will have radiographic (i.e., X-ray) evidence of significant joint breakdown by the age of 65.4
Researchers have found that two major risk factors associated with declining joint health and increased joint discomfort are age and overweight/obesity,5,6 and the degradation of joint tissue is thought to be precipitated by a number of factors, including oxidative and inflammatory stress.7–9
With regard to the latter, inflammatory stress can result from a number of factors, including excess body fat and poor diet. While it’s commonly viewed as a static depot for unwanted and unsightly body fat, adipose tissue is a dynamic tissue that secretes a large number of hormones and chemicals (e.g., cytokines)—many of which have a pro-inflammatory effect and favor an inflammatory environment.10–12 As a result, obesity is commonly recognized as a chronic, low-grade inflammatory state.
“These chemicals can influence the development of [joint discomfort],” says Dr. Jeffrey N. Katz, a professor of medicine and orthopaedic surgery at Harvard Medical School and Brigham and Women’s Hospital in Boston.
This effect can be seen in the numerous studies that have linked being overweight to joint discomfort in non-weight-bearing joints (e.g., hands). “Obviously, you don’t walk on your hands, so there may be something that is produced by fat cells in the body that causes the joint to break down more rapidly than it might otherwise,” says Dr. David Felson, a professor of medicine and epidemiology at Boston University School of Medicine.13
Of course, body weight has a direct impact on the amount of pressure placed on joints, and it’s estimated that a force of 3 – 6 times one’s body weight is exerted across the knee when walking. In other words, being just 10 pounds overweight can mean an additional 30 – 60 pounds of force on the knee with each step.14
While studies show that being overweight can increase joint discomfort, research suggests that even small amounts of weight loss can improve joint comfort.15,16 In fact, researchers have found that, for every 11-pound decrease in body weight, a woman’s risk of osteoarthritis decreases by a whopping 50%.
In addition to unnecessary body fat, excess calorie consumption (which is inherently associated with increasing body fat stores) and poor food choices (e.g., heavily processed and refined carbohydrates, low-quality, refined oils) also promote both acute and sustained inflammatory stress.17–19 This pattern of eating and its associated dietary composition lead to an overproduction of free radicals and pro-inflammatory cytokines, which result in oxidative stress and inflammatory stress. On the other hand, diets rich in fruits and vegetables—which are abundant in antioxidant phytonutrients—are inversely associated with inflammatory stress.20
While inflammation is a fashionable “buzzword,” it’s important to point out that inflammation is the normal, protective, and (usually) temporary response of the immune system to pathogens and injury. In other words, a normal, healthy, and acute inflammatory response is not only a good thing, it’s imperative to optimal human health and function. However, it’s when there’s recurrent stimuli or poor regulation of the system that chronic inflammation—and problems—ensue.
This also highlights the role that something referred to as pattern overload can also play in the breakdown of joint tissue and joint discomfort. According to Paul Chek, pattern overload “describes injury to soft tissues resulting from repetitive motion in one pattern of movement, or restricted movement in one or more planes of motion.”21 While it’s beyond the scope of this article to discuss movement assessments, mobility drills, and proper programming, it’s important to keep this in mind. Don’t just do something because you’re “supposed to” or because that’s how you’ve always done it. Be mindful and listen to your body.
While physiological aging (also referred to as senescence) is inevitable, researchers believe that age may be tied to declining joint health for a number of reasons. One factor that may lead to age-related changes in joint structures is the formation of advanced glycation end-products (AGEs). AGEs are the result of the addition of carbohydrates to proteins or lipids (i.e., fat), and they can be formed both inside and outside the body. For instance, AGEs can be created during cooking (especially high-heat cooking), and they can also be formed by the body after exposure to high levels of blood sugar, which results from regular consumption of simple sugars and refined carbohydrates, as well as poor insulin sensitivity and carbohydrate tolerance.22
AGEs can wreak havoc on the body’s tissues, including joint structures. For instance, AGEs can impact the mechanical properties of cartilage, and as a result, increase joint stiffness, increase joint fatigue, and inhibit the building of new, healthy joint tissue.6 What’s more, AGEs increase free radical formation, impair antioxidant defense systems, increase oxidative stress, and promote inflammation.23
Along those lines, excessive free radical production leads to oxidative stress, which is “a disturbance in the balance between the production of reactive oxygen species (ROS) and antioxidant defenses.”24 Oxidative stress has long been thought to play a central role in cellular senescence and the aging of various tissues, including joint structures.25,26 ROS (i.e., free radicals) appear to play an important role in joint tissue breakdown and promoting inflammatory stress, and as a result, supporting the body’s defense systems through increased antioxidant intake seems to be imperative to bolstering joint health.27
The Fabric of Body Armor
Currently, most people turn to options like acetaminophen and non-steroidal anti-inflammatory drugs (NSAIDs) to relieve joint discomfort, reduce stiffness, and improve physical function. While these tend to be effective in the short-term, regular, consistent use of NSAIDs has been found to be associated with a number of adverse health outcomes, including GI discomfort, enhanced risk for GI bleeding, hypertension, congestive heart failure, renal insufficiency, and more.28–30
With that said, more and more people are recognizing and seeking out the power of functional foods and nutraceuticals to help nourish joints. According to renowned joint health expert Dr. Jason Theodosakis (“Dr. Theo”), “We now know that certain foods can actually help ease and promote joint comfort.”31
Antioxidants play a tremendous role in fighting free radicals, and as mentioned above, excessive free radicals and oxidative stress may be damaging to joints and can contribute to joint discomfort. According to Dr. Theo, foods that contain vitamin A (e.g., beta-carotene), vitamin C, vitamin E, and/or selenium (collectively known as the “ACES”) are powerful weapons for combating free radicals and supporting superior joints.
Speaking of antioxidants, phytonutrients (e.g., flavonoids, anthocyanins, carotenoids, plant sterols, glucosinolates), which are found in an array plant-based foods, can have a prodigious impact on joint health by supporting the body’s antioxidant defense systems, reducing oxidative stress, and promoting a healthy inflammatory response. In addition, a number of other micronutrients (e.g., vitamin D, vitamin K, several B vitamins) may play a critical role in optimizing joint health and function.32
What’s more, certain fatty acids (e.g., omega-3 fatty acids) are protective by nature, promote a healthy inflammatory response, and ease joint discomfort.
With all of that in mind, I’d like to share with you a list of foods that can help nourish joints, support superior joint health, and promote joint comfort. Throughout, you’ll see a common theme of whole foods that are rich in potent antioxidants, support a healthy inflammatory response, and promote a robust immune system.
While the following sections highlight unique attributes of single foods, bear in mind that, in the grand scheme of things, how you look, feel, and perform are the product on your entire body of “nutrition work.” In other words, there’s no single magical food. Instead of viewing foods in isolation as “good” or “bad,” think about “deep health” as the result of practicing healthy eating habits, creating a positive food environment, and choosing high-quality nutritious foods in appropriate amounts regularly and consistently over time.
Going back to the “listen to your body” mantra, it’s also important to consider your own personal responses to foods. For instance, you might find that an otherwise perfectly healthy food (e.g., FODMAP-containing foods) might result in joint discomfort. While it’s beyond the scope of this article, identifying personal food sensitivities—defined as a negative physiological reaction to a food—can play a critical role in easing joint discomfort, as it’s not at all uncommon for specific foods (on an individual basis) to lead to joint flare-ups.
Cherries
The rich red color of the flesh of cherries can be attributed to their rich concentration of anthocyanins, which have an antioxidant potential superior to vitamin E.33 These potent polyphenols promote a healthy inflammatory response by inhibiting the activity of a class of enzymes in the body called cyclooxygenase (COX). Inhibition of COX is a common target of NSAIDs to ease joint comfort and reduce stiffness, and the COX inhibitory activities of the anthocyanins from cherries have been shown to be comparable to that of commonly-used NSAIDs.34
Studies dating all the way back to the 1950s have suggested that cherry consumption may play a role in easing joint discomfort, and as a result, cherries have long had a reputation for supporting joint health.35 This long-standing belief was fortified in a study published in the Journal of Nutrition in which researchers found that the consumption of 45 cherries provoked a significant decrease in circulating levels of urate (i.e., uric acid) in women.36 When urate accumulates in joints, it is associated with discomfort, stiffness, and swelling.
Studies have also shown that regular consumption of cherries can significantly reduce circulating levels of a compound called C-reactive protein (CRP), a marker of systemic inflammation, and significantly reduce the risk of joint flare-ups.37,38 In recent years, tart cherry juice, which has been shown to decrease levels of urate and CRP, promote more restful sleep, soothe sore muscles, reduce joint stiffness, and improve physical function.39–42
Extra Virgin Olive Oil
Extra-virgin olive oil is naturally abundant in a polyphenol called oleocanthal, which has been shown to promote a healthy inflammatory response. Specifically, oleocanthal acts as a “natural anti-inflammtory compound” by inhibiting the activity of cyclooxygenase (COX) enzymes, a property it shares with the highly-recognizable NSAID ibuprofen.43,44
Not surprisingly, researchers have found that a Mediterranean diet, which is rich in olive oil, confers a number of health benefits, some of which seem to overlap with those attributed to NSAIDs.45,46 Mediterranean diets typically provide up to 40% of total calorie intake from fats—up 50% of which comes from monounsaturated fats (predominantly extra-virgin olive oil).47
In addition to oleocanthal, there are a number of other polyphenols (e.g., oleuropein, hydroxytyrosol) in extra-virgin olive oil that provide antioxidant activity and promote a healthy inflammatory response.48 In fact, Italian researchers have found that oleuropein, a compound that is similar in structure to oleocanthal, exerts anti-inflammatory effects and has the potential to mitigate joint degradation.49 Olive oil fortified with hydroxytyrosol has been shown to significantly improve the inflammatory response and reduce joint swelling in animals.50
It’s also important to choose the right type of olive oil. In one study, researchers divided healthy participants into three groups, each one receiving a meal with a different type of oil: Extra-virgin olive oil (EVOO), olive oil (OO), or corn oil (CO). The researchers found that only when the folks consumed meals with EVOO (not OO or CO), they experienced significant decreases in inflammatory markers (e.g., TXB2, LTB4) along with increases in markers of antioxidant capacity within two hours of the meal.51 While the EVOO and OO had nearly identical fatty acid compositions, the EVOO contained nearly 38 TIMES more health-promoting polyphenols.
Avocados
Avocados are a rich source of antioxidant and anti-inflammatory compounds, including various vitamins (e.g., vitamins A, C, and E) and phytochemicals (e.g,. lutein, zeaxanthin, phytosterols, phenolics).52 In one study published in the American Journal of Clinical Nutrition, researchers from Oregon Health and Science University found that fruits and vegetables rich in lutein and zeaxanthin (the primary carotenoids in avocados) are associated with decreased risk of cartilage defects.53
A number of studies have demonstrated that supplementation with avocado-soybean unsaponifiables (ASU), which are concentrated extracts of these plants’ phytosterols, may promote joint comfort. Supplementation with ASU has been shown to lead to reduced NSAID usage, increased mobility, reduced joint discomfort and stiffness, and overall improved functional capacity.54,55 They phytosterols in avocados appear to work by reducing the production of multiple pro-inflammatory compounds (e.g., IL-1ß, TNF-α) and suppressing the activity of two key pro-inflammatory enzymes (i.e., COX-2, iNOS), which are tied to joint breakdown and discomfort.56
What’s more, the addition of avocado or avocado oil to other vegetables appears to promote greater absorption of their antioxidant phytonutrients. In a study published in the Journal of Nutrition, researchers found that when avocado or avocado oil was added to salsa, the absorption of fat-soluble carotenoids was up to four times higher than when the salsa was avocado-free, and when avocado was added to salads, the absorption of carotenoids was up to 15 times higher than when the salads were consumed avocado-free (i.e., fat-free).58
Apples
The skin of apples is rich in antioxidant phytonutrients, including anthocyanins and quercetin.59 Much like the former, quercetin has been shown to promote a healthy inflammatory response that is associated with easing joint discomfort.60 Researchers from La Trobe University in Australia also found that quercetin can prevent the loss of aggrecan, which is a key component of joint tissue structures.61
Not only that, quercetin has been shown to help promote healthy carbohydrate metabolism by inhibiting digestive enzymes like alpha-amylase and alpha-glucosidase, which are responsible for breaking down carbohydrates into absorbable sugars.62 This has implications on joint health because poor carbohydrate management is associated with AGE formation and increased joint discomfort, stiffness, and swelling.63
Regular apple consumption has also been shown to promote a healthy body weight and reduce levels of CRP, a marker of systemic inflammation that is commonly elevated in situations involving joint discomfort.64–66
Blueberries, Strawberries & Other Berries
Just like cherries, blueberries, strawberries, and other berries get their dark, deeply-colored hues from their concentrations of potent polyphenols called anthocyanins.67–69 Much like cherries, the anthocyanins found in berries have been shown to inhibit COX enzymes, thereby promoting a healthy inflammatory response and easing joint discomfort.34
A number of studies have shown that berry consumption has been associated with reduced markers of systemic inflammation. In one study, researchers found that folks who consumed two or more servings of strawberries per week (about 16 strawberries) were 14% less likely to have elevated levels of CRP, a marker of inflammatory stress that may be closely related to joint flare-ups.70 The polyphenols in blueberries have been shown to reduce the body’s ability to create new fat cells, increase anti-inflammatory molecules, reduce oxidative stress, accelerate recovery, and reduce soreness.71–73
Researchers from the Department of Food Science and Nutrition at Laval University in Quebec found that people who consumed a low-calorie cranberry juice cocktail daily for 4 – 12 weeks showed decreased levels of various markers of inflammation as well as a reduction in levels of matrix metalloproteinases (MMPs), which are enzymes involved in the breakdown of a variety of tissues in the body and are thought to play a pivotal role in joint degradation.74–76
Red Wine
Over the last several years, the health benefits of moderate red wine consumption have become increasingly clear, and among the myriad advantages appears to be joint protective effects. Like many of the other dark, rich-colored fruits already discussed, red wine is a rich source of antioxidant polyphenols, including anthocyanins.77
One of the best-known polyphenols found in red wine is resveratrol. A number of studies have demonstrated the anti-inflammatory activity of resveratrol and its ability to promote a healthy inflammatory response, mostly through inhibition of the COX enzymes.78,79 Resveratrol also seems to modulate the body’s inflammatory response by reducing both the production of inflammatory molecules as well as the formation of free radicals.80 What’s more, resveratrol has been shown to protect joints from cartilage damage associated with AGEs, which can reduce collagen synthesis and increase the activity of MMPs, leading to stiffness and joint tissue breakdown.81–83
While resveratrol seems to be the most popular antioxidant associated with red wine, the beneficial effects of red wine cannot be solely accounted for by it. Researchers from Hungary demonstrated that malvidin, the most abundant anthocyanin polyphenol in red wine, possesses potent antioxidant and anti-inflammatory activity, and the effects of malvidin “at least partially account for the positive effects of moderate red wine consumption.”84 Thus, moderate amounts of red wine—1 – 2 glasses per day for men—may be optimal. It’s important to note, however, that drinking alcohol in excess appears to increase the body’s production of pro-inflammatory molecules, according to researchers from the University of North Carolina.85
Coldwater Fish
Coldwater fish (e.g., anchovy, herring, mackerel, sardine, salmon, trout, tuna) are abundant in the essential omega-3 fatty acids EPA and DHA, which the body cannot produce them and must be consumed through dietary sources. Unfortunately, the modern food supply is largely void of these important healthy fats and rife with omega-6 fatty acids.
Experts estimate that throughout human history the optimal ratio for consumption of omega-6 fatty acids (e.g., linoleic acid) to omega-3 fatty acids (e.g., alpha linolenic acid, DHA, EPA) was about 2:1 or 1:1.86 With the contemporary diet, this ratio has shifted dramatically in favor omega-6 fatty acids to 20:1.87 While there are multiple explanations (reductions in healthful seafood consumption), researchers attribute this in large part to the ubiquity of vegetable oils (e.g., soybean oil) present in the Western diet.88 Excessive consumption of omega-6 fatty acids coupled with a deficiency of omega-3 fats is connected to an increase in all conditions characterized by inflammatory stress, including joint discomfort and poor joint health.86,89
This is important for a number of reasons, especially when it comes to promoting a healthy inflammatory response. For example, omega-3 fatty acids have anti-inflammatory effects (e.g., suppress IL-1ß, TNF-α, and IL-6) whereas omega-6 fatty acids do not.90 In fact, studies show that omega-6 fats promote inflammation, particularly when they are consumed in excess of omega-3 fats.91 The omega-3 fatty acids EPA and DHA appear to help ease joint discomfort through their actions on promoting a healthy inflammatory response.92
Studies have shown that diet interventions designed to decrease the ratio of omega-6 to omega-3 fats results in various favorable effects on metabolic and inflammatory profiles (e.g., reductions in IL-1ß, TNF-α).93 When reviewing the body of evidence, researchers from Harvard Medical School have concluded that supplementation with omega-3 fatty acids significantly reduces joint discomfort and stiffness.94
Broccoli and Other Cruciferous Veggies
Broccoli (along with other cruciferous vegetables) is rich in a compound called sulforaphane, which has been shown to promote a healthy inflammatory response and support joint health.95 Sulforaphane blocks the action of enzymes (i.e., MMPs) that result in joint tissue breakdown and provides superior joint protection by promoting a healthy inflammatory response.96–98
In addition to sulforaphane, broccoli is an excellent source of vitamin C. In fact, among the cruciferous family, which also includes cauliflower, Brussels sprouts, kale, cabbage, and bok choy, broccoli is the most concentrated source of this potent antioxidant, providing over 100% of the daily Dietary Reference Intake (DRI) in single one-cup serving. Epidemiological studies have shown that folks with the highest intake of vitamin C showed the greatest joint protective effects and lowest incidence of knee discomfort.99 While vitamin C is typically viewed simply as an antioxidant, it’s important to note that vitamin C plays a significant role in the synthesis of collagen, a major component of many connective tissues including cartilage and bone.100
On top of these joint protective nutrients, broccoli is also an excellent source of vitamin K, providing over 200% of the DRI in a one-cup serving. Vitamin K plays an important role in bone and cartilage mineralization (i.e., the process of creating new bone and cartilage), and several studies have found a link between low levels of vitamin K, poor joint health, and joint discomfort.101–103
Brazil Nuts and Other Nuts
Brazil nuts are one of the most concentrated sources of the micronutrient selenium, which serves a critical role in the body’s antioxidant defense systems, and studies have shown that Brazil nut consumption can significantly improve antioxidant status and increase the activity of glutathione peroxidase, a family of enzymes whose main task is to reduce oxidative stress.104–106 Researchers from the University of North Carolina have also found that there may be a direct connection between low selenium intake, poor joint health, and the severity of joint discomfort.107
In addition to Brazil nuts, walnuts and pecans are among the plant-based foods with the highest content of total antioxidants.108 Nuts (especially walnuts and pistachios) are among the best sources of vitamin E, and research has shown a connection between vitamin E intake and joint health.99 Walnuts are also one of the better plant-based sources of omega-3 fatty acids, specifically alpha linolenic acid (ALA), which is considered to be the “parent” omega-3 fatty acid to the aforementioned EPA and DHA. Cashews are an excellent source of copper, which is necessary for the synthesis of elastin and collagen, proteins that provide the framework for healthy joint structures; studies have linked low copper intake to joint discomfort and declining joint health.109,110
Dairy, Yogurt, and Other Fermented Foods
There’s a common misconception that dairy products may lead to joint discomfort and stiffness. However, the body of evidence suggests otherwise; in fact, there’s a robust body of research to suggest that dairy may ease joint discomfort and reduce joint flare-ups. This really shouldn’t come as much of a surprise, as higher intakes of specific nutrients from dairy (e.g., calcium, B vitamins, protein, magnesium, vitamin D) are linked to improved bone health and muscle function, which may enhance joint protection.111,112
Not only that, studies show that dairy intake is inversely associated with body fat percentage, abdominal fat, body mass index, waist circumference, and hip circumference.113 Studies find that folks who regularly consume dairy experience less joint discomfort, fewer joint flare-ups, and decreased joint tissue breakdown over time.114–116 Observational studies have also shown that dairy consumption is associated with lower concentrations of uric acid.117
While dairy may help ease joint discomfort and promote joint health, fermented dairy (e.g., yogurt, kefir) and other traditionally-fermented foods rich (e.g., sauerkraut, pickles, miso, tempeh) in healthy bacteria may provide even greater benefit. As has been discussed, there are a number of factors (e.g., oxidative stress, inflammation, overweight/obesity, AGEs, aging) that may contribute to declining joint health and joint discomfort, and more and more researchers are beginning to speculate that the gut microbiome may also play a role.
In fact, Dr. Jose Scher, a rheumatologist at New York University, has published a number of studies showing that the gut microbiome of folks who regularly experience joint discomfort and flare-ups is characterized by dysbiosis.118,119 Dysbiosis refers to microbial imbalances on or within the body. In other words, dysbiosis describes the state of an unhealthy imbalance of bacteria in the gut flora, characterized by excessive levels of pathogenic bacteria, inadequate amounts of commensal and probiotic bacteria, and/or reduced bacterial diversity.
This connection between gut dysbiosis and joint discomfort makes sense, as healthy bacteria serve a wide array of functions in the body, including regulating and supporting a healthy immune system and promoting a healthy inflammatory response by producing anti-inflammatory cytokines (and down-regulating pro-inflammatory cytokines).120,121 Supplementation with a probiotic (Lactobacillus casei) daily for 8 weeks has been shown to significantly improve joint health, reduce the production of several inflammatory chemicals (e.g,. TNF-α, IL-6, IL-12), and improve overall inflammatory status.122
Superfoods for Superior Joints
As highlighted above, there are a number of factors that appear to contribute to declining joint health and joint discomfort, and the great news is that research shows that many of these can be managed through dietary choices and lifestyle behaviors. In other words, promoting joint health, supporting joint comfort, improving physical function, reducing joint stiffness, and decreasing joint flare-ups may be well within your control, starting with the food choices that you make.
The superfoods outlined above are nutrient-dense, and they are rife with vitamins, minerals, antioxidant phytochemicals, anti-inflammatory nutrients, healthy bacteria, and more. Consider adding more of these whole foods, which support a strong antioxidant defense system, a healthy inflammatory response, and a robust immune system, to your nutrition arsenal to bolster joint health. Also, pay close attention to how your body responds to your overall diet to help identify if specific foods lead you to experience joint discomfort, flare-ups, and stiffness.
Tim lives with his beautiful wife Amie in Austin, Texas, and he is the Director of Nutrition and Exercise with BioTRUST Nutrition, which develops and distributes a line of premium, scientifically-backed nutrition supplements. Tim earned his Master’s degree in Exercise Physiology from the University of Texas, he is a NSCA Certified Strength and Conditioning Specialist, and he is a Precision Nutrition Level 2 nutrition coach. You can read other articles written by Tim at his blog, and he can be reached by e-mail at tskwiat@BioTRUST.com.
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