Arthritis condition is one of the major problems for many elders around the world. Arthritis can be of many types but the most common type among aged people is osteoarthritis. This condition results from degradation of cartilage of the joints. Cartilage is found between the joints and it acts as a protein cushion in between the bones.
Joints which bear larger weight of the body like knees, hips, spine, feet and hands are the most commonly affected. This disease can occur with advancement of age when the amount of water increases in the cartilage and the protein present in the cartilage starts to degrade.
It can also be caused due to gout, diabetes, hormonal disorders, obesity, and birth defect in the joints and injury in the joint area .
Soybean for osteoarthritis
Soybean or Glycine max has been known as the golden bean and it belongs to genus Glycine. Glycine is also a name of the simple amino acid which makes up the protein structure. This herbaceous plant belongs to the legume family and it was first cultivated in the southeastern part of Asia. The plant is harvested for its seeds and pods which are eaten all around the world. The pods of the plant are used as fresh vegetable in Asian cuisine and salads. Soybean is highly rich in healthy oil and protein which is processed in various products .
Soy proteins are known to have important beneficial components which include genistin, isoflavones and diadzin. These impart anti-carcinogenic, anti-oxidant, anti-inflammatory and many more properties to the plant. It has recently been identified as a potential treatment for bone related diseases including osteoarthritis. The isoflavones in the soy plant have been reported to protect the bones from harmful effects which can damage them and lead to conditions like arthritis.
The osteoblasts or the bone cells are found to be degraded in condition of osteoarthritis. However, one study reported that on treatment with soy extract, it was observed that the genistin in the soy was able to trigger the activity of the alkaline phosphatase (enzyme) which subsequently unregulated the activity formation of osteoblast in the animal model. This reversed the process of bone degradation and stimulated formation of bone cells .
In numerous studies soybean has been used in combination with avocado to investigate the effect of these two components on osteoarthritis. One such study used the soybean extract present in higher proportion and avocado extract present in lower proportion to study the effect on osteoarthritis.
They reported that the extract was able to show positive effect on the osteoarthritis condition by suppressing the effect numerous inflammatory components in the cells and tissues. The extract was able to suppress the activity of interleukin 1 (inflammatory protein expressed by white blood cells) and up regulate the synthesis of collagen in the articular chondrocytes (cells found cartilage). This subsequently slowed down the progress of the condition .
The soybean extract was able to suppress the activity of interleukin 1 beta on the cells of the synovial fluid which triggered inflammation. In addition to this, it also inhibited the action of other interleukins (IL-6, IL-8) and prostaglandins (PGE2- inflammatory proteins derived from fatty acids).
Another important action of this serum extract containing soybean was the ability to up regulate the expression of TGF or transforming growth factor beta (protein which controls proliferation and differentiation of cells) and PAI-1 (plasminogen activator inhibitor-1 also a coagulation factor) by the chondrocytes (cells found in cartilage). When administered orally, there was reduction in the lesions formation in the cartilage in the rabbit models triggered with osteoarthritis condition.
Consequently, there was an increase in the reconstruction of the subchondrial structure of the bone. A similar study investigated the effect of soybean extract on dog models which had osteoarthritis condition. They reported that after giving these animals the extract there was a significant reduction in the development of osteoarthritis cartilage as well as lesions in the subchondrial bones. There was also an observed reduction in the damage caused to the cartilage matrix in the joints .
It has been reported that several protein and their enzymes are involved in catabolism of the cartilage in the osteoarthritic condition. One such protein is MMP-13 (matrix metalloproteinase-13) which is important for degradation of type II collagen in the cartilage (connective tissue in the joints).
Another protein ADAMTS4 and ADAMTS5 are also involved in the degradation process in the cartilages. The enzymes of these proteins cleave the protein structure of collagen and cause damage the structure of the cartilage. When these dog models were given doses of soybean extract there was significant down regulation in the expression of the synthesis of protein MMP-13 in the cartilage. The extract was able to impart protection against the degradation of the calcified cartilage .
The cartilage of a person suffering from the osteoarthritis condition has been reported to contain excess amount of nitric oxide in it. This nitric oxide is produced when cytokines (inflammatory proteins) are stimulated by the iNOS enzyme (enzyme involved in the production of nitric oxide).
This nitric oxide accumulates in the synovial fluid and the synovial tissue. It plays a major role in formation of arthritic lesions in the joint tissues by suppressing the synthesis of the macromolecules in the cartilage matrix. This consequently leads to death of the chondrocytes and reduction in the extracellular matrix. The nitric oxide could also upregulate the activity of the MMP-13 protein. The extract of soybean inhibited the action of the iNOS enzyme subsequently suppressing the downstream processes associated with it .
The compounds present in soybean are known to have anti-inflammatory, anti-oxidant and analgesic properties. Several studies have reported soybean to be effective for treating knee and hip osteoarthritis. By taking the soybean extract regularly for 6 weeks the patients reduces the usage of conventional drugs which are given for treatment .
Another study reported the anti-osteoarthritic properties of the soybean extract by stating that soy extract could suppress the activity of the interleukin-1 and up regulate the synthesis of collagen. They also reported that the soy proteins were able to trigger the synthesis of aggrecan (component of cartilage) and other components of the cartilage matrix.
There was a reduction in the production of pro-inflammatory mediators (proteins which promote systematic inflammation) from the osteoarthritic chondrocytes followed by reduction in the catabolic activities. In addition to this, the study also suggested that the extract was able to stimulate the repair mechanism in the cartilage by its action on the subchondrial bone osteoblasts (bone cells) .
Another study investigated the effect of the soybean extract on horses which had the osteoarthritic condition. After giving the treatment of the soy extract to these horses for 70 days, it was observed that there was reduction in several symptoms which were prominent in the osteoarthritic conditions.
They reported that there was a significant reduction in the erosion of the articular cartilage and hemorrhage in the synovial fluid. In addition to this, there was an increase in the synthesis of glycosaminoglycan (enzyme) in the articular cartilage. These results showed that the extract was able to modify or alter certain proteins while treating this condition .
A similar study in the form of clinical trials was carried out in patients suffering from the osteoarthritis condition. These people were given the combined extract of avocado and soybean with the larger art of the extract containing soybean. The studies were carried out for 1 to 2 years to study the long term effect of this extract on the joints of these patients. It was observed that in one of the subgroups of these patients there was a significant change in the width of the joint space in the pelvis.
The loss of the joint space has been observed in people who are severely affected with the osteoarthritic condition and this extract was able to reduce the width of the joint space in some of the people indicating that soybean extract could be beneficial for the long term treatment. However, the authors indicated that the extract is highly beneficial for a short term treatment however, for a long term treatment there is a need to conduct a detailed study to verify their findings .
How to take soybean in diet
Soybean is one of the common components of the used in Asian cuisine. It is used in curries and eaten in various forms. Soy can be eaten as whole soy also called edamame, or in the form of tofu. This tofu of soy is very popularly added to salads, shakes and other dishes like pasta or stir fry vegetables. Numerous soybean products are also available in the market which includes soy milk, soy yogurt, soy cheese, soy butter and soy nuts.
In Indian cuisine the soybean is added to the curries as a whole for its flavor. It is also available in a crumbled for in the market which is cooked as a dish which is very popular in India. Another form in which soy is available is miso which is mixture of a grain like rice or barley and soybean fermented paste. Tempeh is also a form of soy which contains soybeans cooked with grains which is then cultured in an edible mold.
Soybean oil is also easily available in the market which is considered a healthier option for cooking and deep frying. This oil is also used as an oil base in salad dressings, mayonnaise and margarine. Most doctors recommend soy products to patients suffering from various types of bone and joint related problems .
How much can you have?
Soy food products and its oils based products are considered safe for consumption for people of all ages. However, supplements of soybean are not generally recommended for children as there are no studies conducted on the children. For adults, approximately 20 to 80 grams of soy protein is recommended for daily consumption. It should be noted that this soy protein has low amount of saturated fat and cholesterol. Some experts have specified that 50 grams of soy protein daily is safe to main a good bone health in individuals suffering from bone related issues like arthritis .
Although most of the food products containing soybean is highly beneficial for health, some people might be allergic to soy products. Thus, certain precautions should be kept in mind while consuming soybeans or soy products. It has been reported in a study that women who are suffering from breast cancer should avoid taking soy supplements and products as it can interfere with the medicines which are used for treating the cancer.
In addition to this, people with kidney diseases should also avoid taking soy products as they contain very high level of potassium and phosphorus. In rare cases, the soy products can lead to hypothyroidism as it can lower the iodine level in the body. Other mild side-effects which can result from excess consumption of soy products include stomach problem, diarrhea and constipation .
Soybean is emerging as a much healthier and safer alternative for treatment of arthritic conditions including osteoarthritis. This miracle food is very commonly used as a food item in numerous food products and it is also eaten as a whole bean. Soybean is known to contain anti-inflammatory and anti-oxidant properties which enable it to treat conditions like osteoarthritis.
The soy protein is able to suppress various inflammatory proteins and its mediators which trigger swelling and inflammation in the joints. Many studies have reported that soy proteins are highly beneficial for treatment of osteoarthritis as it tends to slow down the progression of the disease.