Circadian Rhythms and Your Health Video Brigham and Womens Hospital

you at the medical chronobiology program we study the role of the security system and its disruption on health and disease questions we investigate are for example why do people have an increased risk for heart attacks in the morning why is asthma severity worse at night as compared to today and why is epilepsy more prevalent at certain times a day than the other other questions we are very interested in relates to why our shift workers at increased risk for obesity diabetes and cardiovascular disease and then what applies to everybody might it be of importance not just what we eat but also when we eat for our health and our disease risk circadian rhythms are rhythms that are generated by the body even if you place an individual in a constant environment and with constant behaviors then there are many parameters in the body that still oscillate with the 24-hour ethnicity so the circadian rhythms are a product of the body clock the biological clock is composed of a central clock in the brain called the suprachiasmatic nucleus in the hypothalamus as well as virtually all the cells in our body that contain the same molecular machinery that can generate 24-hour rhythms ways in which the circadian system can affect our health one is the normal functioning of the body clock when we are normally entrained to the light-dark cycle and we're living in one timezone in this scenario the circadian system can regulate many physiological parameters and in that way can make people more or less susceptible at particular times a day for adverse events for example in the morning hours we have shown that the internal body clock regulates blood clotting and thereby may contribute to the observed increase in in the morning time for heart attacks heart attacks stroke and sudden cardiac death another example is nocturnal asthma so for a long time people have looked at behavioral factors to explain why people have worse asthma at night so for example is it because people are asleep is it because they are lying flat we've been investigating whether it's actually the internal body clock that may drive pulmonary function and thereby contribute to asthma being worse at night and we have shown that indeed this is the case such that pulmonary function even if your environment and your behaviors are the same will show a very large day/night pattern which worst pulmonary function at night in collaboration with Marta garlotte's from Murcia Spain we have found that the timing of food intake matters for people when they try to lose weight so we found that when people eat their main meal earlier in the day that they lose about 25% more of their body weight during a 20 week long intervention a weight loss intervention we've also found that meal timing is very important in glucose control so we've found that in the morning hours when you eat the same meal that your glucose control is quite good but in the evening hours it's not this was known before but we've now shown that the circadian system plays a dominating role and this morning evening difference we've just shown that in conditions where we D synchronize the internal system with the behavioural system that this causes a worsening of glucose tolerance so the ability of blood sugar to be taken up from the bloodstream into the tissues is less effective the other thing we have shown is that misalignment between the behavioral rhythm and the internal circadian system causes an increase in blood pressure and also increase in inflammatory markers so together these could help explain why there is an increased risk for obesity diabetes and cardiovascular disease in chief workers so where we're heading next is we're looking at the use of food timing as a countermeasure against the adverse detrimental effects of misalignment and this is especially targeted towards shift workers because shift work will never go away but it's also of relevance to basically all of us so whether if we switch the timing of food intake we can actually have a novel therapeutic approach that can help in manipulating not just what we eat but also when we eat to improve our all health you