Arthritis

N. L. is 55, but she’s had problems with pain in her joints
since her early 40s. Her biggest problem is her knees. It
hurts to walk, so she’s decreased her exercise and is
gaining weight. Ibuprofen helps the pain, but it’s starting
to irritate her stomach. The man at the health food store
recommended some supplements with glucosamine
and chondroitin, and she asks you if it’s worth trying.
There are multiple types of arthritis, with differing
pathophysiologies. The nutritional issues vary with
the type of joint disease.
The most common type of arthritis responsible for
symptoms of the large weight-bearing joints is osteoarthritis.
The most common cause of this “wear and
tear” arthritis is obesity. Patients who are overweight
or obese, who complain of pain in the knees and/or
hips, should attempt to lose weight. A combination of
calorie reduction and a regular pattern of non-impact
exercise provides better improvement in function and
pain than weight loss or exercise alone.101
Gout is a metabolic disease in which acute joint
inflammation is caused by uric acid crystals in synovial
fluid. Dietary strategies which reduce serum uric
acid levels may be useful in decreasing the frequency
of recurrences. Urate production for any individual
appears to vary directly with body weight; hence,
weight loss is recommended. Central obesity has been
shown to have a significant effect on gout occurrence
independent of BMI.102 Higher levels of meat, seafood,
and alcohol intake are all associated with
increased risk of gout.102,103 Overall purine and protein
intake have not shown this association. While
limited protein intake was once a standard of therapy
for gout, high-protein diets have a uricosuric effect
and may actually reduce serum uric acid levels.103
Consumption of low-fat dairy products, as well
as fruits and vegetables, appears protective.102,103
A limitation of the evidence is that most studies have
been performed on men.
Numerous supplements are promoted for help in
controlling arthritis pain. Evidence varies as to their
safety and efficacy, as does the methodologic quality
of reported studies.
Glucosamine appears to be safe and effective, and
may stimulate cartilage growth. Taken in doses of
1500 mg/day, it reduces pain and improves function
in patients with knee or hip osteoarthritis, and may
also be helpful in other forms of arthritis (evidence
level B).104 Glucosamine may relieve joint pain from
osteoarthritis as well as NSAIDs, with fewer side
effects.104 However, this was not confirmed in a recent
randomized clinical trial.105 Glucosamine is available in
several forms; the sulfate is the most studied. Since it is
derived from shellfish exoskeletons, there is a theoretic
risk of reaction in those with shellfish allergies.104,106
Concerns about glucosamine increasing insulin resistance
are waning,104 but monitoring of glucose levels in
diabetic patients is appropriate.
Chondroitin is often sold in combination with
glucosamine, but has not consistently been found to
improve symptoms (evidence level B).107 One recent
randomized controlled trial suggests benefit from combined
glucosamine and chondroitin for moderate-tosevere
osteoarthritis only.105 Because chondroitin is
usually derived from bovine cartilage, there is concern
of possible contamination with prions that cause
bovine spongiform encephalopathy (BSE, aka mad
cow disease).106 Preliminary research also suggests
that chondroitin may stimulate growth in prostate
cancer cells.104 The safer approach is to use glucosamine
sulfate in a single ingredient preparation.
S-adenosylmethionine (SAMe) may also be effective
in reducing osteoarthritis symptoms, comparably
to NSAIDs (evidence level A).104,106 High cost, low
bioavailability, and poor product quality make it
impractical for general use at this time. Avocado/soybean unsaponifiables may reduce
pain and slow joint space loss in osteoarthritis (evidence
level A). “Unsaponifiable” refers to the residual
after hydrolysis of fatty acids in avocado and soybean
oil. Use of this supplement appears to be safe for up to
two years.104
Omega-3 fatty acids reportedly suppress inflammatory
cytokines, thereby producing an anti-inflammatory
effect which may be helpful in rheumatoid
arthritis (evidence level A).104 Taking fish oil may
reduce morning stiffness, but relief may not be noted
for up to 12 weeks. Doses over 3 grams per day should
be avoided due to antiplatelet effects and risk of
bleeding.
Gamma linolenic acid is contained in evening
primrose, blackcurrant, and other oils. Some research
suggests that these seed oils may be beneficial for
rheumatoid arthritis, but study quality is variable
(evidence level B).104 Onset of effect may not be seen
for up to 6 months.
Preliminary research has suggested that people with
low vitamin D levels have more pain and disability
from osteoarthritis than people with sufficient vitamin
D, so supplements could be considered for those without
sufficient sunlight exposure.104 Dietary intake high
in antioxidants (such as beta-carotene and vitamins
C and E) might slow progression of osteoarthritis.106
Numerous other dietary supplements have been
suggested for arthritis pain, including cat’s claw, devil’s
claw, stinging nettle, phellodendron, ginger, willow
bark, turmeric, green tea, quercetin, and resveratrol.
There is not yet sufficient evidence to support the use
of these

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