Surgeon Scarlett Mc Nally writes: In the 30 and more years since I qualified, England has had 14 obesity strategies including 689 policies. In that time the prevalence of obesity has almost doubled from 15% in 1993 to 28% of the adults in the UK in 2019. This spectacular failure of policy is probably due to a misplaced focus on individual behaviours rather than social, fiscal, or regulatory policies.
High body mass index is the fourth leading risk factor for disease in the UK and a major risk factor for 13 cancers. People with obesity are 7 times more likely to develop type two diabetes, contributing to worsening health and the risk of amputations, sight loss, kidney dysfunction and complications of surgery.
Several aspects of physiology are not widely understood or applied. First, starchy carbohydrates such as bread, pasta, rice and potatoes, are rapidly converted to sugars that are preferentially stored as fat.
Release of the hormone insulin is triggered by high sugar levels, helping to store sugar as fat and leading to the post meal dip in blood sugar around two hours later. Fats, proteins and fibre cause a lower insulin spike, leaving us feeling fuller for longer. This is the basis of low carbohydrate diets.
Second, the balance of hormones means our bodies are either storing fat or using it. Any food intake reduces fat loss for some time. This is the justification for intermittent fasting routines.
Third, it takes 20 minutes to feel full after eating. Slower eating helps us to avoid overeating at meals, helps us consider portion sizes more wisely and helps us resist second helpings.
Fourth, exercise help the body to burn fat by lipolysis.
So what do we do with this knowledge? Perhaps suggesting what and when to eat is a better option than new, expensively promoted semaglutide injections, which mimic a hormone that decreases appetite.
Replacing carbohydrates means that more protein, fat, or fibre is needed. This can be difficult in a cost of living crisis, as obesity is highly related to social deprivation. A person is twice as likely to experience obesity (37%) in the most deprived areas as in the least deprived (19%).
Tackling obesity then should include social initiatives to fight deprivation such as healthy school meals.
Our environment needs to change, through improved funding and regulation. It should permit physical activity, with play parks, walkable neighbourhoods, cycle lanes, and low traffic areas.
Commercial food companies should be subject to the full weight of regulations, which should be applied to any junk food advertising. We need initiatives to improve access to affordable, high quality food, which is shamefully poor in many deprived areas.
Obesity should not be considered a “lifestyle” problem. It requires a whole community approach focused on environments, regulation, and funding.
Q: Can you speak to the ability or inability to “cure” T2D? Does it have to do with the loss of the pancreatic beta cells?
A: Yes, it has generally been shown that new-onset type 2 diabetes is easier to “reverse,” meaning that blood glucose levels can be so well managed that it appears diabetes has been cured. Over time, a loss of some insulin-making capacity occurs in people with long-standing T2D, particularly if it has not been well-managed, related both to the impairment of pancreatic β-cell function and the decrease in β-cell mass. (PMID: 27615139)
Q: Isn’t insulin resistance now found to be in T1DM as well?
A: Yes, anyone can develop insulin resistance, and it occurs in at least a third of people with type 1 diabetes as well, although it is not always associated with excess weight gain or overweight. Since people with T1D lack insulin due to the body’s own immune system killing off the pancreatic β-cells, greater resistance increases the total doses of insulin needed (whether injected, pumped, or inhaled). Thus, they have developed characteristics of both types and have “double diabetes.” (PMID: 34530819)
Q: Under lifestyle goals, would you include stress management?
A: Stress management was not assessed in the large multi-center clinical trials on type 2 diabetes prevention, but mental stress can certainly raise blood glucose levels due to the greater release of glucose-raising hormones like cortisol and adrenaline. It certainly would be beneficial to address better ways to manage mental stress as part of lifestyle goals for optimal blood glucose outcomes. (PMID: 29760788)
Q: As each person has their own limitations, how important is it to get a physician clearance and exercise guidelines before working with the client?
A: It really depends on the person’s circumstances. How intense will the planned activities be? Is the person currently sedentary? Has he/she been getting annual checkups to monitor blood glucose management and to check the status of any complications? Does he/she have diabetes-related or other health complications that could be worsened by physical activity? The lower the intensity, the more active an individual has been, and the lower the risk for cardiovascular complications, the less likely medical clearance is absolutely necessary.
The latest ACSM Consensus Statement on activity and T2D will be released in early 2022 in Medicine & Science in Sports & Exercise and states, “For most individuals planning to participate in a low- to moderate-intensity physical activity like brisk walking, no pre-exercise medical evaluation is needed unless symptoms of cardiovascular disease or microvascular complications are present. In adults who are currently sedentary, medical clearance is recommended prior to participation in moderate- to high-intensity physical activity.”
Q: Can flexibility training be used for warmups, or do you recommend it only after the workout?
A: While it is possible to do flexibility training at any point during a workout, joints tend to have a greater range of motion after blood flow to those areas has been increased with a light or short aerobic warmup. It may be prudent to do a quick aerobic warmup, some stretching, the full workout, and then more extensive stretching afterwards for optimal results.
Q: Was there any particular protocol for strength training? sets, reps, periodization? What is considered “intense” resistance work? Would fatigue based off of several sets of moderate intensity be recommended then?
A: That is a tough question, and it depends on who you ask. I have seen a lot of debate over the optimal strength training protocol during the many years I have been in the exercise/fitness world. If people are just starting out with resistance training, they will gain from doing even a minimal amount of training.
Starting out with 1-3 sets of 8 to 10 main exercises that work all of the large muscles groups at a light to moderate intensity is considered appropriate for most older or sedentary adults, many of whom have joint limitations or health issues. Moderate intensity is considered 50%-69% of 1-RM (1 repetition maximum) and vigorous is 70%-85% of 1-RM. Both intensity (fewer reps at a higher intensity) and the number of sets (3-5) or days of training (starting at 2, progressing to 3 nonconsecutive days) can increase over 2 to 3 months. Periodization is usually not undertaken by older adults, but may be appropriate for younger, fitter ones.
Q: Do you have any insight or are aware of any studies that involve high intensity (%1-RM) resistance training and T2DM? Or any studies that compare resistance training volume (Sets x Reps x Load)?
A: Some older studies have determined that glycemic management is improved by supervised high-intensity resistance training in people with type 2 diabetes (PMID 12351469). Others have also found that home-based (and, therefore, unsupervised) resistance training results in a lesser impact on blood glucose levels, likely due to reductions in adherence and exercise training volume and intensity (PMID 15616225).
Q: I’m still confused about glucose response to acute exercise. Which is better if you want to bring down your BG right now? Can you speak to the possibility of increased blood sugars with intense aerobic exercise?
A: Most light-to moderate-intensity aerobic exercise will lower blood glucose levels, assuming that some insulin is present in the body. (People who are very insulin deficient may have a rise in blood glucose from doing any activity.) Any activity that gets up into the intense/vigorous range, even if only during occasional intervals, has the potential to raise blood glucose due to a greater release of glucose-raising hormones during the activity. This is particularly true if the activity is short and intense. In individuals with any type of diabetes, declines in blood glucose during high-intensity interval exercise are smaller than those observed during aerobic exercise.
That said, if someone wants to lower blood glucose right now with exercise, it also depends on the timing of exercise. Doing something light to moderate for at least 10 to 30 minutes is the best bet, particularly after a meal when insulin levels are generally higher. Avoid doing intense aerobic or heavy resistance training as those may have the opposite effect. For early morning exercise, any intensity can potentially raise blood glucose due to higher levels of insulin resistance then and lower circulating levels of insulin in the body.
Q: I had an endocrinologist say that long runs or walks are better, and another one said to do a bit of weights.
A: Which activities someone chooses to do should depend on the goal of the training. Is it increased fitness, lowering blood glucose levels acutely, or gaining strength and improving overall blood glucose management? Long, slow aerobic training does have the benefit of increasing cardiorespiratory fitness and lowering blood glucose levels (in most cases). Resistance training, on the other hand, increases muscular strength and endurance and helps people gain and preserve muscle mass, which is where most carbohydrates are stored in the body. It may not, however, lower blood glucose levels, at least not acutely.
Both have their place in a weekly training regimen. Insulin resistance is lowered for 2 to 72 hours following a bout of aerobic training. Resistance training has more of a long-term impact on insulin action by enhancing carbohydrate storage capacity. The best advice is to do some aerobic training at least every other day and some resistance training at least 2, and preferably 3, nonconsecutive days per week. These activities can be done on the same days or different ones.
Adapted from Medscape 5 Dec 2022 by Vinod Rane BS Pharm
Glucosamine, popularly used for osteoarthritis, has previously been found to have anti-inflammatory properties and regular use has now been shown to reduce cancers overall and particularly kidney, lung and rectal cancer.
This was a large prospective study that included 453,645 participants aged 38 to 73 who did not have cancer at the start of the study.
19.4% were taking glucosamine regularly and 80.6% were not. The patients were followed up for a median of 12 years.
Cancer was reduced in cancer overall 0.95, kidney cancer 0.68, lung cancer 0.84 and rectal cancer 0.76.
The study did not include the dose, form and duration of supplement use and there could be a risk that the people who took glucosamine also followed other healthier behaviours than those who didn’t.
My comment: I have been taking glucosamine for 23 years now and it has been a great benefit to my joints. I can see that confounding could be a problem. Non smokers greatly reduce lung cancer, vitamin D users are less likely to get rectal cancer, and slim people are less likely to get kidney cancer.
Zhou J et al Associaton between glucosamine use and cancer mortality. A large prospective cohort study. Front Nutr. 2022;9:947818.
Adapted from Medscape The Male Biological Clock- How to Tell the Time by Mark Trolice MD
Most women know that their fertility declines from the age of 30 onwards. From then on it will become more difficult to become pregnant and there will be an increase in the rate of miscarriage and in infants with chromosomal abnormalities. Yet, due to our modern lifestyles, the availability of contraception and the economic situation, first births in women aged 35 to 39 has increased six fold. To give an increased chance of conception women are increasingly freezing their eggs in their late twenties and early thirties.
Men are also becoming fathers for the first time at later ages. Over the last 40 years this has increased by 3.5 years.
Men over 45 years need five times longer to achieve a pregnancy than men under 25 after their female partner’s age is adjusted for. Sperm counts start to decline from the age of 41 and sperm motility decreases. Chromosomal abnormalities in sperm also increase.
At all ages, being overweight, alcohol consumption, cigarette and e cigarette smoking, can lead to impaired semen production.
The first treatment will be to correct lifestyle factors and then consider ovulation induction and intrauterine insemination. Men over 45 have lower pregnancy rates and higher miscarriage rates with Intrauterine Insemination Treatment.
During IVF cycles injecting the sperm into the egg can improve fertilization rates but in men over 45 there is still reduced fertilization rates and decreased embryo development to the blastocyst stage.
The offspring of older men have higher rates of stillbirth, low birth weight, preterm birth and birth defects. Men older than 40 to 45 have twice the risk of having an autistic child and three times the rate of schizophrenia.
A consideration is that men consider sperm freezing at younger ages, similar to what women do. Another way to tackle the problem is pre-implantation genetic testing of embryos from older men.
Adapted from Independent Diabetes Trust Newsletter March 2023
The National Child Measurement Programme 16 March 2022
In the western world obesity rates continue to climb in children. In the UK when children start primary school at the age of 4-5 14.4% are obese and a further 13.3% are overweight. In Primary 6, at the age of 10-11 25.5% are obese and 15.4% are overweight.
My comment: from my own schooldays, there was only one overweight child in my primary class and she was on steroids and had a heart complaint that stopped her from participating in any exercise. In primary 7, there was one girl who was overweight and she had started puberty earlier than the rest of us.
In the USA in 2019 more than 30% of children were overweight or obese, similar to the UK figures. Physicians are reporting that since the Covid epidemic children are usually between 5 and 10 pounds heavier than they were at any given age, so these figures are likely to worsen even more.
Since 2006 Duke University has treated more than 15,000 children with a restricted carbohydrate diet which encourages the eating of vegetables, fatty fish, nuts and other features of the Mediterranean diet.
Meghan Pauley and colleagues from the Marshall University School of Medicine in Huntington West Virginia have cut the carbohydrate intake for children further to 30g or less a day and have been effective in short term weight loss in severely obese children and teenagers.
The ages of the subjects ranged from 5 years to 18 years. The study lasted 3-4 months. The children were otherwise told to eat as much fat and protein as desired with no limit on calories.
Two groups of analyses were done of different intakes into the programme in 2017 and 2018.
In Group A, 310 participants began the diet, 130 (42%) returned after 3-4 months. Group B had 14 enrollees who began the diet, and 8 followed up at 3-4 months (57%).
Girls compared with boys were more likely to complete the diet. Participants less than 12 years age were almost twice as likely to complete the diet compared with those 12-18 years, however, the older group subjects who completed the diet had the same percentage of weight loss compared with those under 12 years. Group A had reductions in weight of 5.1 kg , body mass index (BMI) 2.5 kg/m2 , and percentage weight loss 6.9% .
Group B had reductions in weight 9.6 kg , BMI 4 kg/m2 , and percentage weight loss 9% . In addition, participants had significant reductions of fasting serum insulin and triglycerides.
This study demonstrated that a carbohydrate-restricted diet, utilized short term, effectively reduced weight in a large percentage of severely obese youth, and can be replicated in a busy primary care office.
Adapted from Medscape, What do we know about intermittent fasting by Carla Martinez Nov 28 2022
A session was dedicated to intermittent fasting at the 63rd Congress of the Spanish Society of Endocrinology.
In animal studies it has been shown that the same number of calories consumed in the morning result in greater weight loss/less fat deposition compared to when the same number of calories are consumed in the late afternoon or evening. Results in humans are less consistent though. My comment: perhaps because they watch television and have well stocked cupboards and fridges!
In humans who ate late, they reported twice as much hunger as the early eaters and energy expenditure and body temperature both reduced by 5%. Thus early eating seems to be more favourable.
Intermittent fasting regimes can very greatly in the window of opportunity allowed for feeding. Researchers found that being consistent with whatever schedule they followed resulted in reduced body weight, an improvement in metabolic efficiency, sleep duration and sleep quality, cardiovascular health, level of mood and quality of life. My comment: so many of us work variable shifts or have different wake and sleep times, feeding times and exercise patternson work days compared to off days.
Caloric restriction with a generous ten hour eating window resulted in weight, blood pressure and lipid improvements in people who had metabolic syndrome. Even in healthy subjects such as firemen who worked 24 hour shifts, limiting food intake to ten hours resulted in a reduction in HbA1c, LDL and diastolic blood pressure.
Dr Labayen is working on the Extreme Project which is testing obese people from Navarra and Grenada in Spain. There are 200 subjects, evenly spread between men and women, and they are advised to follow a Mediterranean diet and consume all their food within an 8 hour eating window. They are divided into early eaters, late eaters and free choice of eating window eaters. How easy the diet is to maintain and its effectiveness on body measurements and any side effects are being measured.
So far there have been fewer side effects than expected with night time hypoglycaemia more pronounced in the early eating group. There is more fat and muscle loss in the time restricted eating subjects compared to a control group who are not restricting their eating time, and the window time has not made any difference. Cardiovascular factor improvement seems to be the most noticeable effects.
Rafael de Cabo PhD, on the other hand primarily works with animals, particularly monkeys and mice. Perhaps, as these animals are not free to cheat on their diet, the effects have shown to be much better than in humans. Fasting has been shown in animals to improve cardiovascular disease, diabetes, cancer, and neurodegenerative disorders. A smaller eating window produces more positive effects than a larger window. Circadian rhythms improve, they eat fewer calories overall, weight and body fat reduces, blood pressure, oxidative stress, inflammation, and arteriosclerosis all are reduced. Hunger is also reduced. These effects occur whether the animals are obese or not. The difficulty is transferring these results to the general public. Currently there are at least 50 human trials underway with increasingly larger cohorts and different forms of intermittent fasting are tried out.
Adapted from Nutrients and exercise affect tumour development by Carla Martinez May 27 2022 and
Three pronged approach may reduce cancer risk in the elderly by Nadine Ekert June 7 2022 Medscape
In a Madrid Oncology conference researchers discussed an update on lifestyle factors and cancer.
Diet and lifestyle can have an influence on each of the successive stages that occur in the development of cancer: initiation, promotion and progression.
A deficit of certain nutrients is one of the factors involved in the initiation stage. Various deficiencies affect different parts of cell metabolism adversely. Such nutrients include folate, B12, B6 and B3, Vitamin C, Selenium, Zinc, Magnesium and Vitamin D.
Aflatoxins from foods of vegetable origin are detrimental. The foods include cassava, pepper, corn, millet, rice, sorghum, wheat, sunflower seeds and peanuts, but the effect very much depends on how these foodstuffs are stored.
Added nitrates to foods such as processed meats and sausages because they become nitrosamines which affect cancer development. Natural nitrates in food however do not cause cancer.
Smoking causes 72% of lung cancer and 15% of all cancers. Eating processed meat causes 13% of intestinal cancers and 1.5% of all cancers. The most problematic foods for nitrosamines are cured meat, and smoked meat and fish. Cooking meats also causes polycyclic aromatic hydrocarbons especially chicken.
Various cooking strategies will reduce the formation or dilute the effects of polycyclic aromatic hydrocarbons.
Marinate mean in an acid solution for more than one hour.
Season meats and fish before grilling them. Good spices to use are: pepper, paprika, garlic, onion, ginger, turmeric, cumin, cinnamon, clove, fennel, and star anise.
Cook at a low temperature eg boiling.
Eat meats with lots of brassicas such as broccoli, cabbage, kale, turnip, brussel sprouts and mustard.
Grilled foods contain benzopyrene which can cause a mutation in DNA and thus cause cancer. Brassicas are rich in sulforphane which works on genes that produce glutathione s-transferase which promotes the elimination of benzopyrene.
Other factors that promote cancer include psychological stress, circadian disruption such as shift work, physical inactivity, obesity, hyperglycaemia, hyperinsulinaemia, gut bacteria disruption, and vitamin D deficiency.
The common factor here is increased inflammation. Some nutrients act as anti-inflammatories including the omega 3 oils EPA and DHA. Ginger, green tea, turmeric and broccoli all help too.
Daily rituals determine our health, so think about how you can optimise your routines.
The influence of exercise on cancer has only been studied in the last ten years.
Hypoxia is one of the main triggers of tumour aggression. Exercise has been shown to improve oxygenation and reduce hypoxia. Physical exercise in combination with chemotherapy has been proven to reduce tumour volume and progression. The best exercises in this regard are those that build up lactate in the muscle such as resistance exercise and cycling.
In the DO-HEALTH study, more than 2,000 healthy elderly people over the age of 70, were observed over three years. A combination of high dose vitamin D, omega 3 fatty acids and a simple home training programme reduced the risk of cancer by 61% compared to placebo.
The risk of getting cancer increases as you get older. Apart from not smoking and sun protection, getting appropriate vaccines and screening, there is not that much left to do. As Vitamin D, omega 3 fatty acids and physical exercise are all promising factors in cancer reduction, various combinations of them were tried. Blood pressure, physical performance, cognition, fractures and infections were looked at. They were divided into 8 groups looking at placebo, training only, and then various combinations and single interventions.
Most groups showed no difference from placebo but the combination of vitamin D, omega 3s and training did. The number needed to treat to prevent one cancer over the three years was 53 which is considered pretty good. Researchers thought the outcome was good enough to recommend this to any one over 70 who was looking to improve their health.
Adapted from: BMJ 3 Sept 22 People need nourishing food that promotes health, not the opposite by Carlos Monteiro et al.
Everybody needs food, but nobody needs ultra- processed food with the exception of infants who are not being breast fed and need infant formula.
The foods that are “ultra- processed” include: soft drinks, packaged snacks, commercial breads, cakes and biscuits, confectionery, sweetened breakfast cereals, sugared milk based and fruit drinks, margarine and pre-processed ready to eat or heat products such as burgers, pastas and pizzas.
These foods are industrial formulations made by deconstructing whole foods into chemical constituents, altering them and recombining them with additives into products that are alternatives to fresh and minimally processed foods and freshly prepared meals.
In low amounts, they wouldn’t necessarily be a problem. But most ultra- processed foods are made, sold and promoted by corporations, typically transnational, that formulate them to be convenient, ready to eat, affordable, due to low -cost ingredients, and hyperpalatable. These foods are liable to displace other foods and also to be overconsumed.
Systemic reviews of large well -designed cohort studies worldwide have shown that consumption of ultra-processed foods increase: obesity, type two diabetes, hypertension, cardiovascular and cerebrovascular diseases, depression, and all- cause mortality.
Other prospectively associated conditions include dyslipidaemias, gout, renal function decline, non-alcoholic liver disease, Crohn’s disease, breast cancer and in men colorectal cancer. They also cause multiple nutrient imbalances.
It is calculated that ingestion of these foods compared to fresh ingredients, matched for macronutients, sugar, sodium and fibre adds a typical 500kcal daily, which leads to the inevitable fat accumulation.
US investigators have found that dietary emulsifiers and some artificial sweeteners alter the gut bacteria causing greater inflammatory potential, so replacing sugar with these isn’t a good idea either.
In the UK policies to limit promotion and consumption of ultra-processed food have recently been rejected, mainly because of the belief that in our current economic situation people need access to cheap food. As no one really wants to support foods that cause illness, the obvious solution is to promote foods that are fresh and minimally processed, available, attractive and affordable. Such a strategy would improve family life, public health, the economy and environment.
Adapted from Medscape, Why our brains wear out at the end of the day, F Perry Wilson Aug 15 2022
We can all recognise from our own experience that as a long day goes on, our performance on mental tasks gets worse. In chess players for example, as the game goes on over several hours, they take longer to make decisions, and they make more mistakes. This is known as cognitive fatigue.
It has been found that the cognitive control centre in the brain is in the left, lateral, prefrontal cortex.(LLFC).
The LLFC is responsible for higher level thinking. It is what causes you to be inhibited. It shuts down with alcohol and leads to impulsive behaviours. It has reduced activity in functional MRI studies as you become more and more cognitively fatigued. The LLFC helps you think through choices. So how does cognitive fatigue happen? As a matter of interest the role of glucose has already been studied and it has been found that this does NOT vary in non- diabetic subjects.
Researchers did experiments with people to induce cognitive fatigue. They had to look at letters and indicate whether the letter was if it was a consonant or a vowel if it was red or if it was upper or lower case if it was green.
Both groups did this for six hours, but one group had much less switching around than the other, so that there was an “easy” group and a “hard” group. They all sounded terribly tedious to me!
The hard group made more mistakes than the easy group, but of course the task was harder to start with. The hard group got a little bit more tired at the end, but both groups were pretty fatigued. The hard group took longer to respond all through the testing hours, but they didn’t take longer by the end of the task. So, overall, there was no clear indicator that could determine who had done the easy tasks or the hard tasks.
The researchers then started adding a new game after the six hours. The subjects were told that they would now play a “reward game”. For instance:
Would you rather have a 25% chance of earning $50 or a 95% chance of earning $17.30?
Would you rather earn $50 but your next task session will be hard or earn $40 and your next task session will be easy?
It has been previously shown that as people become more fatigued they will tend to pick the low- cost choice over the high- win choice. Perhaps we all recognise that after a difficult workday we may be more likely to go with the flow and do something easy rather than the “best” thing. We often don’t feel we have much decision- making power left. I know this is a factor for prescribing more antibiotics on a Friday afternoon.
Interestingly pupil dilatation is a physiologic measure that demonstrates when your brain is “full up”.
When you are interested in something your pupils dilate a little. In the hard group, as time went on, pupil dilatation stopped and constricted in some people. In the easy group however, the dilatation continued through the tasks.
By doing a very fancy labelled hydrogen MRI on the subjects they looked at differences in brain metabolites in the LLPC area of the brain during the tasks.
They found that the level of glutamate and glutamic acid rose in the LLPC but not other metabolites and not in other parts of the brain. They also found that the glutamate leaked from inside the cells to outside the cells.
It is statistically significant that the higher the levels of glutamate in the LLPC, the more likely you are to just make the easy decision as opposed to really think things through.
Perhaps a good night’s sleep is clearing out the excess glutamate in the LLPC and allowing you to perform well the next day.
My comment: The hours pilots and air traffic controllers work are highly regulated because of the effect of fatigue on decisions and performance. Yet, this does not extend to GPs and hospital doctors to anything like the same extent. It is considered important for lorry drivers. For all drivers and for all students, particularly before exams, it is a good idea to recognise that we are all human. Tiredness isn’t something that you can really overcome with will power.