what causes diabetes? diabetes is one of the most confusing health topics on the internet. might
actually be number one. and few questions are more hotly debated and misunderstood than what causes
type 2 diabetes. i wanted to make a video to dispel some of that confusion so i'm very excited to say
we got one of the world's leading diabetologists to talk to us and shed some light on this issue
professor Roy Taylor has been studying type 2 diabetes for almost 40 years. he's a professor of
medicine and metabolism at newcastle university in the UK. he has authored numerous studies and books
on diabetes and he spearheaded the groundbreaking DIRECT trial which showed type 2 diabetes can be
reversed. we started from the very beginning: what causes diabetes? the definition of diabetes is an
elevated glycemia so there's an idea then that it must have been too many carbs were eaten
for glucose to be elevated, for the person to be hyperglycemic. and i have people messaging me
in panic, terrified of eating a piece of fruit or a bowl of oatmeal because it's going to give them
diabetes. so what does the latest science say, do we know what causes diabetes? it's when
a susceptible person acquires too much fat inside the pancreas and so these insulin-producing cells
are struggling for quite a long period of time, that's pre-diabetes, and eventually
they start not being able to function properly and that's diabetes. so what's causing type 2 diabetes?
it's carrying around more fat than the individual can cope with. that's a profoundly important thing.
each of us inherits a very different collection of genes purely by the luck of the draw, and if we say,
well, what's relevant to diabetes? we need to understand something that i would call the
personal fat threshold. so let's just look at a person who is, say, 300 pounds in weight
and yet doesn't have diabetes, hang on, what's going on there? well, his beta cells have
a very high tolerance for fat, they're not phased by the fat being around them and so
that person's threshold to develop diabetes is very high. and then there are some people, 10% of
people with type 2 diabetes in the united kingdom have a body mass index under 25. 25?! they look thin.
so what's going on there? well, our work has shown that it's just the same, it's these people
who are very susceptible to a gain in weight. so what's your personal fat threshold? we can't tell
but we can say if someone's developed type 2 diabetes, they've become heavier than their
own body can cope with. in the consultation, a doctor has one person sitting in front of them
and the advice ought to be directed at that person, so we need to personalize it and understand we've
got a crushingly simple disease happening in complicated individuals. so it could be that those
people are accumulating the same amount of fat, for some reason it's less damaging, they are more
resistant to fat being present inside the pancreas and inside the liver, or it could be that there is
less fat altogether in those organs, have you tease that out? yes, that's absolutely
the case, people with type 2 diabetes do have considerably more fat in the organs than
people of the same weight who don't have type 2 diabetes so there is a matter of quantity
but i think it's quite likely that also there will be a susceptibility at the level of the cell,
so given the same amount of fat, one person may just be struggling with their beta cells
another might be just fine. so we all accumulate fat subcutaneously, under the skin, especially
around the waist and in the hips, it's our love handles, right? but those subcutaneous stores have
a limit and when they're full, the body starts storing that excess fat around the organs in
our abdominal cavity and eventually inside those organs and that's when the mayhem starts. some of
us can store more fat under the skin and can already be pretty overweight and still not
have metabolic issues, while others have limited storage capacity in that subcutaneous compartment
and start putting away the extra fat inside the organs and having metabolic issues
while still being in the normal BMI range, while still looking relatively lean. that's
this key idea of the personal fat threshold. there's also ethnical variation, for example
asian populations generally have a lower threshold so they start having metabolic issues
at a lower BMI. so the idea is that, despite this person-to-person variation on the exact threshold,
the root cause is the same for everybody, excess energy being taken in chronically
and too much fat being stored for that individual's capacity. so the next obvious question
is, are some foods worse than others? do some foods precipitate this process and some protect us?
that's what we turned to next. to summarize this idea of the cause of diabetes, it would then be
an accumulation of too much fat for the individual threshold of the individual
which could come about, correct me if i'm wrong, by overeating calories of any source. too many carbs,
too much fat, too much protein, whatever it happens to be. the body will handle
whatever fuel is thrown at it so if we look at human beings across the world, the diets are very
different in different parts of the world and yet people can become overweight in any part
the body can turn the carbohydrates into sugar as we've already mentioned, that happens with
digestion, but also on into fat, and the body can use fat to burn it in fact in a form that's
similar to sugars but it can also take protein and just turn it straight into carbohydrate or
sugar and so it doesn't matter directly how much carbohydrate a person eats except highly processed
foods are likely to contain quite a lot of carbohydrate, added sugar, because the
manufacturers add it to improve the taste, to get people to buy more, and also they formulate it
in a way that you want to eat more and more, so there is a problem with processed foods
and very high carbohydrate foods, certainly sugary foods, so if we were to set those aside for a
moment and say, does it matter if you're eating, say, potatoes or fruit, which contain carbohydrate,
compared with other non-starchy vegetables? and the answer is, not a lot, but if people are eating the
processed foods or very sugary foods they tend to take in more energy, more food, than they would do
with this nice, healthy, cooking from raw, as it were, so the type of food does matter but really only in
the matter of how much food the body takes in. you can develop diabetes if you ate steak alone, if you
ate enough of it. and so, if people like eating a low-carb diet, that's a perfectly good way of
losing weight or keeping the weight under control. some people like it, some people hate it. again, what
a surprise, we're all individuals, so it's not one size suits all. if we look at all the
studies that have dealt with this very emotional subject of a low carbohydrate diet, we find that
when we put them all together and look at the ones that we can be certain are really solid,
there's precious little difference between low-carb approach and a low-fat approach
so it's worthwhile just sitting back and reflecting on the simplicity
of how we can survive as a species, what foods we actually need and how our incredible bodies will
turn one food stuff into another to be able to cope. again, it's a matter of eating what you like,
but not too much of it. so, this idea of wiggle room that we've touched on so many times in the past
there are some fundamental principles of healthy eating but under that umbrella there's room for
personal variation. along the same lines, there are several valid strategies to maintain a healthy
body weight and we've looked at this topic in some detail before. next time we'll keep looking at our
conversation with professor taylor and the exact approach, step by step, they used in their trials
to reverse diabetes. let me know your thoughts, catch you next time