Dr. Kush Dev Singh Jarial
Type 2 Diabetes mellitus is a chronic metabolic disorder and is a global pandemic of the 21st century.Rapid socioeconomic changes and urbanization leading to changes in lifestyle and behaviour have resultedin an increased incidence of diabetes in the developing world. Complications of type 2 diabetes aredirectly related to the control of blood glucose and duration of diabetes; however, worldwide half of the people living with diabetes do not have good glycaemic control. Lifestyle modifications include dietary modifications, physical activity,and behavioural aspects like stress, smoking cessation, and moderation of alcohol are important factors but poor adherence to lifestyle modifications is common in patients with type 2 diabetes.Any form of behavioural change is difficult to sustain if it is not enjoyable, too rigid/ strict to follow, socially, culturally, and financially unacceptable.
Alternative and complementary system of medicine like AYUSH, yoga, herbal formulations, acupuncture, aromatherapy, etc. has been in use for centuries worldwide for the treatment of chronic diseases like diabetes mellitus. Yoga as a science of healing has been known for thousands of years to mankind and the primary aim of which has been to maintain the balance of the human mind and emotions with the body. Yoga therapy due to its cost-effectiveness and proven benefits in diabetes has been included in the American diabetes association guidelines.
Key defects in the pathophysiology of type 2 diabetes mellitus
Yoga as a therapeutic option formanaging diabetes has been viewed as a cost-effective approach worldwide due to its potential benefits; however, research on its mechanism for diabetes control has gained attention in the past few years.The “Ominousoctet” (bad eight) of diabetes mellitus includes decreased insulin secretion, decreased incretin effect (ineffective intestinal hormones), increased free fatty acids, decreased uptake of glucose in various tissues /increased absorption of glucose from the intestine and kidney, defective neuroendocrine control, increased glucagon and increased glucose formation from liver are eight cardinal defects in the pathogenesis of type 2 diabetes.
Mechanisms of Yoga Therapy on Diabetes Control
Yoga as a therapy for chronic disorders like diabetes is a new and emerging trend. Yoga therapy modulates the ominous octet of diabetes by different mechanisms and helps in controlling glucose control and preventing complications.
Neuroendocrine control
The autonomic nervous system (ANS) through sympathetic (inhibition) and parasympathetic (stimulation) nerves exerts control on the pancreas. Yogic breathing pranayama like bhastrika, bhramari, sheetali/sitkari, chandra andsuryabhedan(left and right nostril breathing)) results in fine-tuning of insulin secretion by regulation of ANS. Yogic asanas involving intensive and strenuous exercise like kapalbhati, bhastrika, and pranayama ( regulated rapid breathing) augments sympathetic activity thus inhibiting insulin release; while mild intensity asanas like mind and body relaxation techniques, slow breathing along with a focus on mind, meditation stimulates parasympathetic activity andreduces sympathetic activity thus regaining and balancing not only the insulin secretion but also endocrine control through the autonomic nervous system through vagal modulation.
Improved insulin sensitivity
Various yogic postures lead to contractions and relaxations of musculature, which leads to increased glucose transporter expression in muscles thus increasing glucose entry in the cells. It also decreases the free fatty acid levels in the blood thus improving insulin sensitivity and its secretion. These asanas also have positive effects on fat metabolism and redistribution in patients with diabetes. Ling mudra, Surya mudra and prana mudra increase metabolic rates promote weight loss thus increasing sensitivity and reducing blood glucose levels.
Decreasing Stress hormones
Chronic stress leads to the sustained rise of stress hormone (cortisol) while acute stressful conditions lead to an acute release of stress hormones. Cortisol has an adverse effect on glucose metabolism and leads to a rise in blood glucose. Asanas like savasana involving breath awareness and deep relaxation control neuronal pathways of endocrine glands thus decreasing stress hormones; thus achieving glycemic control or helping in preventing diabetes. Apan mudra, Gyan mudra, meditation ( dhyan) involving mindfulness “aum” chanting and yoga Nidra etc have beneficial psychological effects, anxiety reduction, better sleep, greater relaxation, more accepting, positive energy and stabilized brain; all of which not only have positive effects on glycemic control but helps in prevention coronary heart disease.
Oxidative stress and Inflammatory cytokines
Diabetes is a state of chronic pro-inflammatory state with evidence of increased pro-inflammatory markers like plasma C-reactive protein, TNF-?, Interleukin-6, etc. in diabetic patients. These markers decrease insulin secretion, increase insulin resistance, and accelerate atherosclerosis and other complications of diabetes. Studies have shown that practicing yoga therapy reduces these markers of inflammation thus preventing diabetes and its complications.
Regulation of insulin and glucagon secretion
Yogic purification/cleansing practices (shatkarmas) like vamandhauti(stomach cleansing), kapalbhati (frontal brain purification) and shankhaprakshalan a(in testinal cleansing)increase the production of insulin thus helping to control blood glucose. Achieving the balance of the autonomic nervous system through rapid and slow yogic practices regulates pituitary gland and hypothalamus functions which modulate the function of insulin and glucagon-secreting cells of pancreas. Surya namaskar performed in brisk and energetic way increases insulin production through brain signaling as this asana increases the cellular requirement of insulin and oxygen. Abdominal contractions and relaxations during asanas (agnisarkriya, kapalbhati)massage the pancreas rejuvenating pancreatic beta cells and stimulating insulin secretion. Pancreatic functions are also improved by yogic practices done in seated postures such as ardhamatsyendrasan, yoga mudra, and mandukasan.
Yoga and mindful eating
Mind-body connection through yogic practices like pranayama, Sudarshan kriya, and meditation leads to self-awareness, self-reflection, and self-change thus improving eating habits/disorders. Improvement in eating habits has consistently shown improvements in dietary intake, modest weight loss, and glycaemic control in people suffering from diabetes. Yoga also encourages the intake of foods like vegetables, which are low in carbohydrates and high in fiber content, which is important in diabetes control.
Yoga should be learned from a trained yoga professional. All yoga asasansinvolve posture manipulation which may be difficult to do for persons with diabetes complications or those who have physical limitations. All diabetic patients practicing yoga should not stretch themselves beyond their physical capacity. Safe yoga styles should be learned and practiced in people with diabetes having complications. Sarvangasan and sheershasan may exacerbate diabetic retinopathy, vigorous or yoga performed in harsh weather should be avoided in patients having cardiovascular disease. Exercise and yoga therapy should not be considered synonymous as yoga therapy emphasizes breath regulation, maintenance of postures, meditation, and mindfulness while doing these practices. Yoga as a lifestyle change is enjoyable, easy to follow, and has no socio-cultural and financial barriers. Evidence suggests that yoga interventions appear to be equal and/or superior to exercise in most outcome measures.
(The writer is Assistant Professor, Department of Endocrinology & Metabolism, AIIMS Jammu).
