I was reading about nutrition, and discovered this device that can measure vitamins C and D:<p>https://www.sciencedirect.com/science/article/pii/S0956566321006278?via%3Dihub<p>What is happening right now in the biosensor space that might allow a more complete nutritional profile to be measured? Could nutritional profiles one day be as easy as testing glucose levels, or be cost-reduced enough to offer as a fringe benefit for blood donors?
I worked for a lot of years in the wearable health sensing field (till about 3 years ago, so I haven't paid as much attention since) and was constantly looking for new kinds of biosensors for wearables. Samsung said they were working on optical sensors for many kinds of health sensing a decade ago; haven't heard much from them about actual products/sensors except this:<p><a href="https://www.sammobile.com/news/samsungs-preparing-to-discuss-new-health-advancements-at-unpacked/" rel="nofollow">https://www.sammobile.com/news/samsungs-preparing-to-discuss...</a><p>Skin impedance across a wide frequency range is interesting, it can tell you something about the composition of the flesh. There has been some use of smartphones for biosensing:<p><a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5713127/" rel="nofollow">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5713127/</a><p>There has been some work on blood sugar detection through the skin using optical sensors, though no one appears to have figured it out yet after years of research. If they do figure it out it could probably be used to detect other things as well. I've never heard of anyone trying to detect other nutrients via sensors, I'm not even sure it can be done via blood samples (there have been blood tests for vitamin D for a long time, and perhaps it is possible to detect other metabolites, but it may not have much practical use for metabolites that are mostly stored in organs, proteins for example, although if you had a continuous record of what was in the blood maybe you could estimate what reaches the organs.) The idea is intriguing though, perhaps metabolite analysis using sensors could finally settle the questions around diet and health once and for all. There are tests for cortisol from saliva (and a variety of other kinds of saliva tests) although they are fairly expensive for frequent use:<p><a href="https://www.amazon.com/s?k=cortisol+test" rel="nofollow">https://www.amazon.com/s?k=cortisol+test</a><p>There are a variety of expensive medical tests for many specific chemicals that are important to nutrition and health. Making those tests cheap and non-invasive is a challenge. I don't know if anyone is even working on it, medicine tends to choose research topics very strangely. Like for decades a universal flu vaccine was considered too difficult. Now suddenly there are several candidates. A lot of the time I think lack of invention is a direct consequence of a lack of trying (and yet we waste PhD's on manipulating markets and charge people to get educations).<p>This is one place you could look for answers:<p><a href="https://www.mdpi.com/journal/sensors" rel="nofollow">https://www.mdpi.com/journal/sensors</a><p>Anything related to sensors tends to show up in that journal.