Wednesday, June 22, 2016

Sugar, Fat, You, Your Bacteria, And Measuring It All

From a User Experience point of view, the problem with dieting is that the delay between cause and effect. If being hungry for a little while immediately showed an effect in fat stores, we'd all be sporting six-packs as we be able to regulate losing fat effectively. It also would be very likely that being lean would not be so desirable for being too easy to attain.

Right now the diet pendulum has swung back from fat being the enemy, and the new diets are focussing on sugar. While touting different benefits and restrictions, the basic thinking behind the low-sugar diets is that consuming certain simple carbohydrates create insulin spikes, and those are what wreak havoc with the body, from shunting energy directly into fat cells to contributing to metabolic syndrome.

But what food create these insulin spikes? As far as we know, the amount of sugar, or simple carbohydrates, in relationship to things like fiber, protein, or fat in every food changes how the body responds. This is expressed in a crude scale for every individual food called the Glycemic Index, tested by giving some under controlled circumstances to a group of people and measuring their blood glucose--and then repeat for every food.

A few problems with that:
  1. The GIs are all tested in isolation from each-other, while we usually eat a bunch of foods together, so we can't really predict the actual spike from the ingredients in a meal.
  2. The glucose spike actually does not fully correlate with the insulin spike, which is what we actually want to lower.
  3. And worst: turns out glucose spikes are highly individual, as the same meals create very different spikes in different people.
Number 3 is what everyone who has family members of very different body composition always suspected: some people really can eat the same foods as others and not get fat. Thoughts are that our gut flora (part of the microbiome) plays a role, but there's not enough real data on that.

That scientific study on individual spikes was done with a technology called Continuous Glucose Monitoring, developed specifically for diabetics. It consists of sticking a long, thin needle through your skin (you may not want to do a Google image search) and leaving it there for days on end connected to a little box stuck to your skin that displays the body glucose data. The more recent version don't connect to a display but beam the data to a display. CGMs help diabetics significantly to regulate their blood sugar, as the continuous readings give a lot better insight into their bodies which allows them to dose and time their insulin better.

CGMs have been unwieldy, expensive, and unpleasant; sticking a long needle in your abdomen is not fun, even for diabetics who understand the benefits. The NHS here in the UK will not pay for it, or only make it available for two weeks or so at a time, as the cost-benefit ratio was not quite there. But technology doesn't stop, and CGMs just got a whole lot cheaper and easier to use.

Recently I met someone who is using a new system that makes inserting the sensor easy and far less invasive, and makes doing the read-outs much easier: you just hold a reader the size of a phone to the sensor and you get the last few hours of continuous data that you can then view in charts and graphs. It looks like the data is locked inside that reader, but the techs I was with already found out it uses NFC to communicate, so I doubt it will take long before other NFC-enabled computers like phones will be able to read body sensor out and then allow users to slice, dice and upload the data. Most importantly, the system is a lot more affordable than what was previously on the market, and seems at most 10% less accurate than the gold standard. Running costs seem to be under £60 per sensor that can last up to two weeks. That's not cheap, but a lot cheaper than previous systems.

At this level of cost, measuring your glucose actually becomes cost effective for fitness-oriented people who are serious about quantifying something about themselves that is far more fundamental for body composition than steps and runs, even if you did it for only a month. Combine the readings with photographs of everything that you eat, and you can make an individual analysis of how you react to foods. In a month you can do plenty of experiments with your standard diet, low-carb days, low-fat days, weekends and holiday eating, favourite restaurants, or individual foods and dishes to get more insight into how your body responds. This kind of insight would make the effects of food real and measurable for an individual, but also not have to overly restrict themselves as current diets that block out whole food groups do. It is easy to see how a trainer or nutritionist could set themselves up with a reader and offer two weeks or a month of exploratory monitoring as a service to multiple clients.

The next step would be to then for a lot of people to upload that data and look for patterns, possibly exploding a lot of food myths or creating whole new ways of categorizing people into the different ways they metabolize food (and guaranteed finding out some of those classic GI measurements were plain wrong, or not holding up for large populations). A company could offer itself as a GI testing service for new foods, sending its test panel a new product and asking them to upload their glucose data for a period before, during, and after consumption, to possibly create a new seal of approval. We'll also then find out everything is really Not That Simple, and that many other factors, like our gut bacteria, make nutrition quite hard to grasp on an individual level--and then companies will try to make that quantifiable too.

As with every measurement, humans will try to game them for their own ends, either to make their food products seem 'healthier', or cheat on their own diets that they should stick to, or many other ways. But for many motivated people there now is a new tool to create a more direct feedback loop and get more insight into how what they eat makes them achieve, look, and feel.