Strawberries Improve Pain and Inflammation in Obese Adults with Radiographic Evidence of Knee Osteoarthritis

[Sly Saint]

Abstract
Osteoarthritis (OA), the most common form of arthritis, is a significant public health burden in U.S. adults. Among its many risk factors, obesity is a key player, causing inflammation, pain, impaired joint function, and reduced quality of life. Dietary polyphenols and other bioactive compounds in berries, curcumin, and tea have shown effects in ameliorating pain and inflammation in OA, but few clinical studies have been reported. The purpose of the present study was to examine the effects of dietary strawberries on pain, markers of inflammation, and quality of life indicators in obese adults with OA of the knee. In a randomized, double-blind cross-over trial, adults with radiographic evidence of knee OA (n = 17; body mass index (BMI): (mean ± SD) 39.1 ± 1.5; age (years): 57 ± 7) were randomized to a reconstituted freeze-dried strawberry beverage (50 g/day) or control beverage daily, each for 12 weeks, separated by a 2-week washout phase (total duration, 26 weeks).

Blood draws and assessments of pain and quality of life indicators were conducted using the Visual Analog Scale for Pain (VAS Pain), Measures of Intermittent and Constant Osteoarthritis Pain (ICOAP), and Health Assessment Questionnaire-Disability Index (HAQ-DI) questionnaires, which were completed at baseline and at weeks 12, 14, and 26 of the study.

Among the serum biomarkers of inflammation and cartilage degradation, interleukin (IL)-6, IL-1β, and matrix metalloproteinase (MMP)-3 were significantly decreased after strawberry vs. control treatment (all p < 0.05). Strawberry supplementation also significantly reduced constant, intermittent, and total pain as evaluated by the ICOAP questionnaire as well as the HAQ-DI scores (all p < 0.05). No effects of treatment were noted on serum C-reactive protein (CRP), nitrite, glucose, and lipid profiles. Dietary strawberries may have significant analgesic and anti-inflammatory effects in obese adults with established knee OA.

Strawberries Improve Pain and Inflammation in Obese Adults with Radiographic Evidence of Knee Osteoarthritis - PMC (nih.gov)

 

[Sly Saint]

I'm not obese, but I am getting regular strawberries from the garden at the moment..........shall have to wait and see if it helps with joints

 

[Milo]

I guess that one could add a layer of sliced strawberries to go with the double cheeseburger with bacon and find the 20$ bank note between the lettuce and the pickle and clue in they have to declare less pain when the questionnaire ask them to

But what about the non obese osteoarthritis patients? load them up with strawberry sugar drink too or stick to their regular diet?

 

[Hutan]

How many a day, on what dosing schedule?

The participants were consuming the equivalent of 1 kg of fresh strawberries a day during the strawberry phase. Which is a hell of a lot of strawberries.

The powders were supplied by the California Strawberry Commission, but I didn't see evidence of there being conflicts of interest among the researchers. I didn't try hard to find them though.

I didn't see any obvious problems with the study on a quick read, and I was expecting to. The authors claim that blinding was maintained. Even if it wasn't, the decreases in the three inflammatory markers are significant.

So yeah, home grown strawberries sound pretty good. I note this though:

USDA tests found that strawberries were the fresh produce item most likely to be contaminated with pesticide residues, even after they are picked, rinsed in the field and washed before eating. For these reasons, strawberries continue to be at the top of the Dirty Dozen™ list.

https://www.ewg.org/foodnews/strawberries.php

 

[Jaybee00]

In general I’m not against “big agriculture”, but the commercially produced strawberries in the USA are generally large and flavorless, and I tend not to buy them. When I was younger I believe that the strawberries tasted much better.

 

[Jonathan Edwards]

Even if it wasn't, the decreases in the three inflammatory markers are significant.

Maybe, but inflammatory markers are not known to be associated with OA as far as I know so maybe strawberries are just IL-6 blockers of no relation to joints.

The slightly worrying thing is that CRP is driven by IL-6 so it is difficult to know why IL-6 should go down without CRP. CRP is effectively the bioassay for IL-6!

 

[Jonathan Edwards]

And I am a bit sceptical that someone would not notice that they are eating a kilogram of strawberry mush - as opposed to placebomush.

 

[Hutan]

were randomized to a reconstituted freeze-dried strawberry beverage (50 g/day) or control beverage daily

Each intervention was for 12 weeks, with and intervening two weeks of washout phase. During the active treatment phase, the participants consumed 50 g of freeze-dried strawberry powder reconstituted in water twice a day. This dose of strawberry powder is equivalent to approximately 500 g of fresh strawberries, and was previously used in another study [24]. The control powder was formulated to match the sensory properties of the strawberry powder as well as its caloric value and macronutrient composition.

Just for the sake of correctness - I read the text as meaning that the 50g of powder was consumed twice a day. It is ambiguous but it seemed the best interpretation. I see however that the abstract suggests that the 50g of powder was the total daily dose. So, probably the daily dose was 50g of powder, so the equivalent of 500g of strawberries, not 1 kg.

The slightly worrying thing is that CRP is driven by IL-6 so it is difficult to know why IL-6 should go down without CRP. CRP is effectively the bioassay for IL-6!

That's interesting to keep in mind as we look at Long Covid papers. So, if we don't see IL-6 and CRP moving together, then that would be surprising?

I read a bit of this, suggesting that IL-1B should also be correlated.
From CRP to IL-6 to IL-1: Moving Upstream To Identify Novel Targets for Atheroprotection

Moving upstream in the inflammatory cascade from CRP to IL-6 to IL-1 provides novel therapeutic opportunities for atheroprotection that focus on the central IL-6 signaling system and ultimately on inhibition of the IL-1β producing NLRP3 inflammasome.
Cholesterol crystals, neutrophil extracellular traps (NETs), atheroprone flow, and local tissue hypoxia activate the NLRP3 inflammasome. As such, a unifying concept of hsCRP as a downstream surrogate biomarker upstream IL-1β activity has emerged.