Preventive Neurology

Since stating my intention to join the  #BackTo21  campaign to get my BMI back to what it was when I was 21 years of age, I have had several emails and direct messages on social media questioning the wisdom of my intention.  Photo by NeONBRAND on Unsplash It is clear that despite BMI being a relatively poor metric of health there is overwhelming evidence that at a population level it predicts poor health outcomes. Importantly there is new data that indicates the target BMI for the prevention of type 2 diabetes and the metabolic syndrome depends on your ethnicity. For people of South Asian origin, there is a call to reset the BMI cutoff to 23.9, which for most people is within the normal range. At the same time, there is a call to classify obesity as an important social determinant of health. Arnaud Chiolero argues below for using BMI as a socioeconomic indicator. Do you agree? Isn’t it quite amazing that in a previous era corpulence was a sign of affluence, whereas in th...

Photo by i yunmai on Unsplash It looks like we have to rethink what a healthy BMI is!  This study below shows that above a BMI of 23 kg/m2 there is a linear increase in risk of severe COVID-19 leading to admission to hospital and death, and a linear increase in admission to an ICU across the whole BMI range, which is not attributable to excess risks of related diseases. The important thing to point out is that the relative risk due to increasing BMI is particularly notable in people younger than 40 years and of black ethnicity . This means that if your BMI (weight/height (m)-squared) is above 23 you should probably do something about it. In parallel to this, I read an article a few weeks ago that said you need to get back to what you weighed when you were aged 21. If I did this I would need to lose 13kg (2 stones) and my BMI would be 22. So I am going to get on the case and will be joining the #BackTo21 challenge and in so doing maximising my chances of doing okay if I ever get...

Photo by engin akyurt on Unsplash "I was told to try the Snack-All-Day diet plan, but it has been a disaster. I was eating 7 or 8 small snacks per day but instead of losing weight, I have gained weight. Why?"   It is quite clear that obesity is a major public health problem and contributes to a substantial burden of disease at a population level. Why do we get obese? This is complex, but a lot of it can be explained by the food environment we live in and the change in our eating habits over the last 3 or 4 generations. The study below shows that the extent of the postprandial dip in glucose, which occurs 2-3 hours after a meal predicts hunger, a shorter time until the next meal and greater additional energy intake at 3-4 hours.  The reason why we get low blood glucose 2-3 hours after a meal is that there is too much insulin released relative to the amount of sugar or glucose in the baseline meal. In other words, our bodies produce too much insulin in anticipation of the...

From Kevin Boyd Is it not interesting that obesity, and its associated comorbidities, are associated with a higher lifetime prevalence of all-cause dementia? However, is it obesity that is a causal factor or the fact that obesity is strongly associated with (1) reduced exercise and a sedentary lifestyle, (2) hypertension and metabolic syndrome (insulin resistance), (3) systemic inflammatory syndrome, (4) mental health problems (depression/anxiety) and (5) sleep apnoea and other sleep disorders? All five of these factors may be the causal factor and not necessarily obesity itself. The modern epidemic of obesity is been driven largely by a change in our diets in particularly the ubiquitous consumption of processed and ultra-processed foods and the large increase in sugar (sucrose) consumption. Prior to the Victorian era, sugar was not a dietary staple and we tended to eat large quantities of unprocessed foods. Eating unprocessed foods meant we had to work hard at chewing food, which crea...

Picture from AllGo - Unsplash Good and bad news. It is clear that the pharmaceuticalization of obesity means its treatment will need to be long-term. Should the emergence of so-called glucagon-like peptide-1 receptor agonists as a treatment for obesity be celebrated? Yes, if you have vested interests in the pharmaceutical industry and you think the long-term risks of these treatments are less than the comorbidities associated with obesity. No, if you think obesity can be managed successfully with lifestyle and behavioural modifications. The study below of once-weekly subcutaneous semaglutide shows that if you stop the drug after 20 weeks the treatment effect of continued weight loss is reversed and the inevitable weight gain The class of glucagon-like peptide-1 receptor agonists increase the production of insulin. Insulin lowers the blood sugar level, enhances the growth of β cells in the pancreas, which is the site of insulin production. The downside of increased insulin production is...

I am often criticised for politicising medicine. Some people believe that medicine and politics shouldn’t mix. However, as soon as you realise that social determinants are the best predictor of clinical outcomes in most diseases you realise medicine and its practice has to be politicised. How do we as individual healthcare practitioners change the social determinants of health outcomes without the help of politicians? Obesity may be a lifestyle disease, but it is clear that most people who are obese can’t help it. In other words, they are obese because of their circumstances. “But people’s ability to take personal responsibility is shaped by their circumstances. People cannot take responsibility if they cannot control what happens to them.” Michael G. Marmot,  The Health Gap: The Challenge of an Unequal World Obesity is a risk factor for many diseases including all-cause dementia and multiple sclerosis. This is why it is so important for us to think about ways to reduce obesity. I...

Obesity is a hot potato topic. People who are overweight don’t want to be fat-shamed. However, it is now evident that given our current environment, which favours a sedentary lifestyle and has a different food landscape to the one our species evolved in, that obesity is a disease. Yes, a metabolic disease that is associated with systemic inflammation, which puts obese people at risk of a large number of diseases including multiple sclerosis and dementia . We estimate that about 10-15% of incident cases of MS could be prevented if we could prevent childhood and adolescent obesity. This is easier said than done. Obesity is now one of the major social determinants of health (SDoH). Obesity is strongly linked to deprivation and lower socioeconomic class. Why? Because cheap food is to blame. I have little doubt that most obesity is attributable to the imbalance in our macronutrient content and the relative excessive consumption of processed and ultra-processed carbohydrates.  Changing ...