Joint Health
Introduction
As we age there is an increasing tendency for our joints to become less flexible and less mobile with the resulting stiffness causing mild to severe discomfort.
Risk Factors For Progressive Joint Inflexibility and Osteoarthritis:
Age – the risk becomes greater as we age, particularly over the age of 45.
Gender – risks are relatively greater for males below the age of 50 and for females above the age of 50.
Previous injury or wear – previous injury to a joint, especially the knee, will increase risk of problems later in life.
Obesity – being overweight places more stress on load bearing joints, particularly the knees.
Heredity – having parents and/or siblings with joint problems increases risk.
Nutrients and Joint Health
There is now substantial evidence that some nutrients have specific benefits in helping to maintain the health of joints, and thereby delay and/or reduce levels of stiffness and pain, and increase both flexibility and ease of movement. These nutrients are normally either absent or undersupplied in the typical UK diet and as such the possibility of supplementation of these nutrients is an option worthy of consideration.
A brief review of the nutrients which have specific joint health benefits are outlined below. They have been divided into those where there is substantial evidence of benefit and those where benefits have less proof.
Nutrients with substantial evidence of benefit:
- Glucosamine and Chondroitin
- Omega-3 (Fish and Cod Liver Oils)
Nutrients with some evidence of benefit:
- MSM
- Turmeric
- Ginger
- Vitamin D
Nutrients with Substantial Evidence of Benefit
GLUCOSAMINE
Of the nutritional factors which are promoted for joint support glucosamine ranks as one where the evidence of positive effect is substantial – so much so that in some countries it is now being viewed more as a medicine than a nutritional factor. Glucosamine is an essential building block of a substance known as glycoaminoglycans (GAGs) which forms the basis of all cartilage tissues. Glucosamine works by stimulating the repair and renewal of cartilage tissue.
Numerous studies have now been undertaken to test the effects of glucosamine on joint health and osteoarthritis. The best of these trials were averaged out and the conclusion was made that glucosamine provided moderate efficacy in the treatment of osteoarthritis symptoms.
Recently a large study found that although it was difficult to see effects of glucosamine in people with low level of stiffness and discomfort, significant improvement was found in those people more severely affected.
The level of glucosamine necessary to produce these effects is generally recognised as being 1500mg of glucosamine sulphate or glucosamine hydrochloride per day, and that the period of time generally required for noticeable effects to be first seen is about 6-8 weeks.
Chondroitin is often provided in supplements alongside glucosamine because it is also a component of articular cartilage (which coats the knees and elbow joints) and seems to be particularly valuable in attracting fluid into the cartilage tissue making it more spongy and improving its shock absorbing qualities.
Chondroitin has been shown to have similar properties to that of glucosamine, and while not as not as many trials have been carried out with chondroitin as with glucosamine, the results are somewhat more consistent. For instance in two studies of over 120 people, taking 1200mg of chondroitin per day for 2-3 months resulted in significant reduction in joint pain compared to those who did not take any supplements.
The Combination of Glucosamine and Chondroitin
In a recent large landmark trial, it was found that combining 1500mg glucosamine sulphate and 1200mg of chondroitin sulphate per day for six months resulted in better effects than with either supplement individually. This trial found a significant decrease in symptoms from those suffering from moderate to severe pain at the start of the trial.
The traditional use of cod liver oil goes back for generations and the rationale for this use included general well being, and later as a naturally rich source of vitamins A and D. However, probably the most reported benefit of taking cod liver oil was relief of joint pain and improvement in joint mobility. We now recognise that most of this age related increase in joint pain is associated with osteoarthritis.
Although considerable anecdotal evidence exists for the effects of fish oils on osteoarthritis the bulk of scientific studies have been on the more severe rheumatoid arthritis and these have shown consistent and significant benefits of supplementation of fish oil in reduction of severity of rheumatoid arthritis symptoms. These are summarised below, but indicate that taking an average of 3.8g EPA/DHA for 16 weeks will result in 88% of cases showing a reduction in number of tender or swollen joints, and duration of morning stiffness being reduced in 77% of cases.
Clinical Evidence
Summary Of Randomised Control Trials of Fish Oils On Rheumatoid Arthritis Sufferers from Calder; Am J Clin Nut 2006
| Number of trials | 18 |
| Average daily dose EPA/DHA | 3.84g |
| Average duration of trial | 16 weeks |
| Trials showing significant reduction in number of tender or swollen joints | 15/18 |
| Trials showing significant reduction in duration of morning stiffness | 13/18 |
These results are difficult to argue against and make a strong case for any program of joint health including the provision of a minimum of 450mg of EPA/DHA per day.
Nutrients with Some Evidence of Benefit
MSM
Methylsulfonylmethane (MSM) is an organic sulphur containing compound and is used by the body to maintain normal connective tissue, including cartilage, and may in addition have some anti-inflammatory properties. It is found naturally in a variety of fruits, vegetables and grains, but the richest dietary source is cows milk.
One 12 week trial with 118 osteoarthritis patients found that benefits from providing 1500mg glucosamine suphate per day were increased when combined with 1500mg of MSM. In a second trial over 12 weeks MSM on its´ own at a high level of 6g per day provided a 25% reduction in symptoms of pain, and an increase in joint movement and functionality was observed.
TURMERIC (CURCUMIN)
Curcumin is one of the active ingredients of turmeric which has been traditionally used in Indian herbal medicine for centuries. However, the merits of curcumin are now being proven scientifically, to the point where it is now confirmed that curcumin has significant anti-inflammatory action with very few, if any side effects.
There are several trials which now indicate that curcumin may be of benefit in reducing symptomology in arthritis, and this level of evidence will probably build to become substantial in the near future.
GINGER
One 6 week study evaluated the effects of a highly concentrated extract of ginger species in 261 patients with stiff and painful knees. The results for ginger were only moderately more effective than the dummy tablet used in this study with 50% of the control group and 63% of the ginger extract group reporting a reduction in knee pain.
VITAMIN D
A deficiency in vitamin D may indirectly increase risk progression of joint immobility and possibly osteoarthritis progression by being a causal factor in low bone density.
A major American study of populational trends known as the Framingham Study showed that a low bone density was associated with an increased risk of osteoarthritis progression among persons with knee osteoarthritis.
Overall, the view of the SC expert panel is that the evidence for direct effects of vitamin D may be quite weak, but if a joint support product contains vitamin D along with more proven nutrients then it should be viewed as a worthwhile addition.
ROSEHIP EXTRACT
There has been one reasonably well conducted trial using rosehip extract on patients with arthritis which demonstrated an improvement in mobility and reduction in pain and stiffness.
The authors of this study suggest that the active ingredient may be a compound they call GOPO. However, there is no other evidience of effect for this compond and the mechanism of effect is unclear. As such the SC Expert Panel feel that products with this ingredient as the active cannot be recommended until further research is available. Nevertheless, this ingredient may be worth trying if the joint health benefits found using the supplements with more evidence are less than expected.
