Relationship Between Diet and Knee Health
While you are developing a plan to thrive and stay active despite having knee arthritis, don’t forget about the impact that foods and diet can have on your knee health. Although there isn’t yet a cure for arthritis, there are many things you can do to help limit the symptoms and continue to live the active lifestyle you desire.
Osteoarthritis, including knee arthritis, results part from inflammation and oxidative stress in the joint. Although there are structural changes that happen to the bone and cartilage, many of the effects (e.g. knee pain and swelling) are due to elevated inflammatory markers and other molecules that cause us to feel pain and result in swelling of the knee joint.
Diet not only has the ability to help us maintain a healthy body weight (which decreases load across the knee joint), some foods can also help block or reduce the inflammation and oxidative stress that cause pain and disability!
Patients often ask “what is the best diet for knee arthritis?” Below are my recommended 8 best foods for knee arthritis, based on the best available medical evidence at the time of publication:
Turmeric is a member of the ginger family. It comes from the rhizome of a plant, Curcuma longa. It has long been used for medicinal purposes in Asian countries. Its initial use is traced back to India, and it then spread to Southeast Asia. Today, it is most often used as a flavoring agent in Asian cuisines, especially in curries.
Turmeric produces substances called curcuminoids that have strong antioxidant capacity. Research studies have those that these curcuminoids can decrease the oxidative stress in patients with osteoarthritis. Researchers believe that these anti-oxidant properties may account for the fact that turmeric helps to relieve osteoarthritis symptoms.
Turmeric’s active ingredient curcumin has been shown to have a similar anti-inflammatory effect to NSAID medications (e.g. Aleve, Ibuprofen). Curcumin can decrease the signaling of molecules that cause inflammation by blocking substances such as NF-κB, IL-1β and IL-18. Clinical studies have shown similar improvements in pain when taking curcumin compared to Ibuprofen, and improved physical function and pain in patients taking curcumin compared to a placebo.
Curcumin has also been shown to block some of the enzymes that break down cartilage in the knee. It has been shown to inhibit something known as matrix metalloproteinases (MMPs). MMPs catabolize, or break down, the cartilage of the knee and lead to the develop of osteoarthritis. Studies have demonstrated that the curcumin found in turmeric blocks these cartilage-damaging enzymes.
2. Olives and Extra-Virgin Olive Oil
Olives and olive oils have long been known to contain anti-inflammatory compounds. In fact, olive oil and its derivatives have demonstrated encouraging anti-inflammatory and antioxidant properties. Three randomized controlled trials (RCTs, the most robust form of medical research trial) have investigated the effect of olive oil and its natural ingredients in patients with osteoarthritis.
These RCTs demonstrated improved pain and function in arthritis patients who received olive extracts or olive oil. This included improved better sleeping at night, better walking, less swelling, better mobility, and less “redness and heat.”
Polyphenols from olive leaves have also been shown to protect cartilage-producing cells through their anti-inflammatory actions. In several laboratory studies, cartilage producing cells, known as chondrocytes, were protected from inflammatory substances when treated with olive extracts. Studies in rats have shown that virgin olive oil components minimized cartilage deterioration and bone erosion in addition to helping with pain and swelling.
It’s not just lab studies that show the potential benefits of olives and olive oils on arthritis. Pharmacokinetic (the study of drug movement through the body) studies have shown that polyphenols (active ingredients of virgin olive oil) can be readily absorbed by humans. The standard intake of olive polyphenols in humans following Mediterranean diets is 200 µg/day, assuming that 30-50 grams of live olive oil is consumed daily; most of the animal studies showing beneficial effects have used higher doses.
However, the multitude of laboratory, animal, and clinical studies suggest that olives and its derivatives show significant potential in preventing cartilage damage due to arthritis and improving knee arthritis symptoms such as pain and swelling.
3. Pasture-raised Farm Eggs
Eggs have been a controversial food when it comes to optimal health. However, more and more recent studies are demonstrating the healthy impacts of eggs, especially eggs from pasture-raised or free-range chickens. Pasture-raised chicken eggs have been shown to have a proportion of omega 3 fatty acids compared to store-bought eggs. They have also been shown to have a high concentration of Vitamin D.
Both omega 3 fatty acids and Vitamin D have been shown to be important in decreasing the pain and symptoms associated with osteoarthritis. Considering that pasture-raised or free-range eggs have higher concentrations of omega 3 fatty acids and Vitamin D, research has suggested that pasture-raised farm eggs are one of the best anti-inflammatory foods patients with knee arthritis can eat.
Certain substances in eggshells have also shown promise in the treatment of osteoarthritis. In the U.S. alone, 600,000 tons of eggshells are produced annually. Due to the high volume of eggshell disposal, researchers have investigated alternative uses of these eggshells. One such study found that eggshell membranes contain important substances for knee cartilage health.
Two such substances include chondroitin sulfate and Hyaluronic acid. Both substances have been used in the treatment of knee osteoarthritis, and methods have been created to separated the membrane from the shell. The OPTION trial demonstrated that arthritis patients treated with “Natural Eggshell Membrane” showed improvements in pain and stiffness.
Salmon is sometimes considered a “super-food” and should definitely be a staple of a healthy diet for many reasons. First, It is rich in omega-3 fatty acids. The benefits of omega-3 fats acids are well-studied and well documented. In general, omega-3’s improve cell function and help the body control inflammation. Fatty acids also help with fullness and weight loss, which limits compressive forces across the knee joint.
Importantly, one-third of the omega-3’s in salmon is in the form of EPA (eiocosapentaenoic acid). EPA is then converted by the body into closely-related substances known as prostaglandins, thromboxjnes, and resolvins. All three of these substances have been shown to help the body fight inflammation.
Salmon is also rich in Vitamin D, an important vitamin for bone and cartilage health. It’s not surprising that many research studies have shown that consumption of salmon and salmon by-products leads to less knee pain in individuals with knee osteoarthritis. Other studies have found found a significant reduction of exercise-induced musculoskeletal joint pain after the consumption of fish oil and fatty fish such as salmon.
Salmon also produce a hormone, or small protein, named salmon calcitonin, which is very similar to human calcitonin. However, salmon calcitonin is more potent than human calcitonin and concentrated varieties of this hormone are often prescribed for various medical issues such as osteoporosis.
Salmon calcitonin has also been shown to be useful for arthritis. In fact, one study showed that people who were naturally predisposed to increased cartilage breakdown actually responded better to salmon calcitonin than patients who weren’t predisposed for progressive arthritis.They had less progression of their arthritis as judged by x-ray than at-risk knee arthritis patients who didn’t receive salmon calcitonin.
Another research study look at applying salmon calcitonin directly to cartilage cells that were taken from individuals with osteoarthritis. Application of salmon calcitonin resulted in increases in the amount of proteoglycans and collagen synthesis in cartilage cells. Proteoglycans are important because they help the cartilage stay hydrated and allow it to withstand pressure. Collagen is a protein that is the major component of cartilage.
Salmon is unique in that it’s anti-inflammatory properties come both from healthy fats (omega-3’s) and proteins (calcitonin). It is important to note that these health benefits are most likely to be present in “wild-caught” salmon as opposed to salmon grown in captivity.
Broccoli consumption leads to the production of a substances called sulforaphane (SFN). SFN has broad biological activity and has been shown to be very important in joint health. SFN decreases the concentration of NF-κB, prostaglandin E2, and nitric oxide, all substances that have been shown to damage knee cartilage.
A recent research study demonstrated that normal dietary brocolli intake results in measurable amounts of SFN not only in the blood, but also in the synovial fluid in the knee. This study is important because it proves that broccoli consumption results in the presence of biologically active compounds within the knee joint that decrease knee cartilage breakdown.
Pecans are a nut from a species of hickory trees that are commonly found in the southern United States. Pecans are low in carbohydrates and packed with healthy vitamins and minerals.
You may be starting to see a pattern here…Once again, pecans are packed with Omega-3’s. The anti-inflammatory benefits of these healthy fatty acids have been discussed at length above when talking about olives, pasture-raised eggs, and salmon. Suffice it to say, omega-3’s are a crucial component of any of the best diets for knee arthritis.
In addition to omega 3 fatty acids, pecans contain high levels of magnesium, calcium, fiber, vitamin E, and zinc – all of which also help the body fight inflammation. In summary, pecans are a must have for any well-balanced diet!
Garlic (Allium sativum L.) is a perennial herb originally from Central Asia, that is now grown worldwide. It has been used extensively as a traditional medicine for cardiovascular, blood sugar, cholesterol, immunological, and multiple other medical conditions. It has also been studied intensely for it’s pain-reducing properties.
One study looked directly at the effect of garlic tablets (1000mg) in obese females with knee osteoarthritis. They found that 12-week supplementation of garlic resulted in less knee stiffness in patients with knee arthritis compared to placebo. However, there was no change in other measures of arthritis symptoms (pain and physical function).
A second study looked at a similar patient population, but examined post-menopausal overweight or obese patients with knee arthritis. This study found that 1000mg of garlic supplementation reduced joint pain scores compared to patients just taking a placebo.
Some studies have suggested that garlic’s pain-reducing effect in patients with knee osteoarthritis are a result of its ability to block or reduce TNF-α. TNF-α is an inflammatory factor that is increased in patients with knee arthritis. Multiple studies and analyses have shown that garlic supplementation led to decreased TNF-α concentrations in patients with knee arthritis. However, other studies have shown no change, so more research is needed.
There have been studies suggesting garlic blocks other inflammatory markers such as IL-6, MMP-13, collagenase, and resisting, all of which are known to break down knee cartilage and increase pain in patients with knee arthritis. Furthermore, garlic has strong anti-oxidant properties. In short, there are numerous anti–inflammatory and anti–oxidant compounds contained in garlic that make it one of the best foods for knee arthritis.
Arugula is a type of leafy green vegetable that has been shown to benefit patients with inflammatory conditions like knee arthritis. Arugula contains multiple bioactive compounds that help suppress inflammation. It contains isothiocyanates and SFN, similar to broccoli, and these have been shown to directly inhibit the breakdown of cartilage cells.
Green leafy vegetables are also good sources of antioxidants such as Vitamin K, Vitamin A, and Vitamin C. These anti-oxidants are important to bone and cartilage health and can help decrease symptoms from degenerative diseases such as knee arthritis.
Arugula is an excellent food to include as you work on creating your best diet for knee arthritis. It is important that you consult with your doctor if you are taking an anti-coagulant, or blood thinning medications, as arugula may interact with them.
Summary of Best Foods for Knee Arthritis
A well-balanced, healthy diet is a crucial part of any plan to address knee arthritis. In addition to being helpful to maintaining a healthy weight and reducing force in the knee, many foods have anti-inflammatory and antioxidant properties that help reduce the symptoms of arthritis. Some have even been show to reduce the damage that occurs to knee cartilage as a result of arthritis.
FAQ. Best Foods for Knee Arthritis
What foods help repair knees?
Multiple foods have been shown to prevent cartilage loss in patients with knee arthritis. Many of these foods are included in the Mediterranean diet. Foods that help repair or protect knee cartilage include turmeric, olives or olive oil, pasture-raised or free-range eggs, salmon, broccoli, pecans, garlic, and arugula.
What foods make knee arthritis worse?
Arthritis is a multi-factorial disease that occurs due to both Biomechanical and physiologic reasons. One of the most commonly implicated factors in the pain and swelling associated with arthritis is inflammation. As such, foods that increase inflammation can be expected to make arthritis worse.
Examples of inflammatory foods include fried foods, sugar, and alcohol. Many of these foods contain excessive and “empty” calories and can lead to increased body weight, which is also bad for knee cartilage.
- Panahi Y, Alishiri GH, Parvin S, Sahebkar A. Mitigation of Systemic Oxidative Stress by Curcuminoids in Osteoarthritis: Results of a Randomized Controlled Trial. J Diet Suppl. 2016;13(2):209-20. doi: 10.3109/19390211.2015.1008611. Epub 2015 Feb 17. PMID: 25688638.
- Messier SP, Mihalko SL, Legault C, Miller GD, Nicklas BJ, DeVita P, Beavers DP, Hunter DJ, Lyles MF, Eckstein F, Williamson JD, Carr JJ, Guermazi A, Loeser RF. Effects of intensive diet and exercise on knee joint loads, inflammation, and clinical outcomes among overweight and obese adults with knee osteoarthritis: the IDEA randomized clinical trial. JAMA. 2013 Sep 25;310(12):1263-73. doi: 10.1001/jama.2013.277669. PMID: 24065013; PMCID: PMC4450354.
- Bharat KT, Manhas NS, Gutcho J, Lin J, Bhattacharyya S, Kounang R. Ingredients of a Natural Oral Nutritional Supplement and Their Role in the Treatment of Osteoarthritis. Clin Med Insights Arthritis Musculoskelet Disord. 2022 Mar 25;15:11795441211063365. doi: 10.1177/11795441211063365. PMID: 35360183; PMCID: PMC8961370.
- Chin KY, Pang KL. Therapeutic Effects of Olive and Its Derivatives on Osteoarthritis: From Bench to Bedside. Nutrients. 2017 Sep 26;9(10):1060. doi: 10.3390/nu9101060. PMID: 28954409; PMCID: PMC5691677.
- Pitaraki EE. The role of Mediterranean diet and its components on the progress of osteoarthritis. J Frailty Sarcopenia Falls. 2017 Sep 1;2(3):45-52. PMID: 32313850; PMCID: PMC7161934.
- Ruff KJ, Winkler A, Jackson RW, DeVore DP, Ritz BW. Eggshell membrane in the treatment of pain and stiffness from osteoarthritis of the knee: a randomized, multicenter, double-blind, placebo-controlled clinical study. Clin Rheumatol. 2009 Aug;28(8):907-14. doi: 10.1007/s10067-009-1173-4. Epub 2009 Apr 2. PMID: 19340512; PMCID: PMC2711914.
- Mendonça CR, Noll M, Castro MCR, Silveira EA. Effects of Nutritional Interventions in the Control of Musculoskeletal Pain: An Integrative Review. Nutrients. 2020 Oct 9;12(10):3075. doi: 10.3390/nu12103075. PMID: 33050122; PMCID: PMC7601187.
- Sondergaard, BC., Madsen, S.H., Segovia-Silvestre, T. et al. Investigation of the direct effects of salmon calcitonin on human osteoarthritic chondrocytes. BMC Musculoskelet Disord 11, 62 (2010). https://doi.org/10.1186/1471-2474-11-62
- Davidson R, Gardner S, Jupp O, Bullough A, Butters S, Watts L, Donell S, Traka M, Saha S, Mithen R, Peffers M, Clegg P, Bao Y, Cassidy A, Clark I. Isothiocyanates are detected in human synovial fluid following broccoli consumption and can affect the tissues of the knee joint. Sci Rep. 2017 Jun 13;7(1):3398. doi: 10.1038/s41598-017-03629-5. PMID: 28611391; PMCID: PMC5469854.
- Dehghani S, Alipoor E, Salimzadeh A, Yaseri M, Hosseini M, Feinle-Bisset C, Hosseinzadeh-Attar MJ. The effect of a garlic supplement on the pro-inflammatory adipocytokines, resistin and tumor necrosis factor-alpha, and on pain severity, in overweight or obese women with knee osteoarthritis. Phytomedicine. 2018 Sep 15;48:70-75. doi: 10.1016/j.phymed.2018.04.060. Epub 2018 May 9. PMID: 30195882.
- Hernández-Cruz EY, Silva-Islas CA, Maldonado PD, Pedraza-Chaverri J, Carballo-Villalobos AI. Antinociceptive effect of garlic, garlic preparations and derivative compounds. Eur J Pain. 2022 May;26(5):947-964. doi: 10.1002/ejp.1935. Epub 2022 Mar 22. PMID: 35263014.
- Rondanelli M, Perdoni F, Peroni G, Caporali R, Gasparri C, Riva A, Petrangolini G, Faliva MA, Infantino V, Naso M, Perna S, Rigon C. Ideal food pyramid for patients with rheumatoid arthritis: A narrative review. Clin Nutr. 2021 Mar;40(3):661-689. doi: 10.1016/j.clnu.2020.08.020. Epub 2020 Sep 2. PMID: 32928578.