FitTech Insider

Why do fitness and health industries need blockchain, Jens Strüker?

Sharing and using personal data securely while retaining control or augmenting the work of doctors: Blockchain will change health and fitness, predicts Professor Jens Strüker, director of Fraunhofer Blockchain Lab. Especially in combination with machine learning.


Professor Strüker, why do the health and fitness industries need blockchain at all?
First, because they can use it to share personal data securely while retaining control over that data. Second, because a huge ecosystem can be built around blockchains. That will include services on a whole new level that we haven't even seen before. It will be gigantic.

Your claim is supported by figures from analysts who predict that the blockchain industry will explode in the coming years. Experts at Gartner, estimate that the business value added by blockchain will grow to$176 billion by 2025 - and $3.1 trillion by 2030 (Source: Tech.co). Why is that realistic?
Today's blockchain technology still has teething problems. Performance is slow compared to traditional databases, especially in public blockchains, which are affected by lack of identity management. For example, I could open 50,000 different accounts without anyone noticing. However, if these initial problems are overcome, and we have promising concepts, then the blockchain industry can take off – meaning that the big revenue numbers of many analysts are not unrealistic.


Jens Strüker at FitTech Summit V: Tech or Die!


On November 8 and 9, 2021, FitTech Summit V: Tech or Die! will take place digitally. At Europe's most relevant conference on the future of fitness and health technology, Professor Jens Strüker will discuss the power of blockchain for fitness. Get your free ticket now!



If I had to explain blockchain to a layman, I would say blockchain is a decentralized and networked database whose copied individual parts control each other. How close am I to the actual scientific definition?
You are not fundamentally wrong. But it is important to emphasize that there is not one “Blockchain”. There are many different blockchain technologies and then many different blockchain networks implemented and running. With the very first one, the Bitcoin blockchain, it is still relatively clear what it can and cannot do. But for many others,it's more diffuse. Take the Ethereum blockchain, for example: not only is information stored there as in a database, but there are also first-time "smart contracts".

Smart contracts?
Actually, the name is misleading because they are neither "smart" nor "contracts." They are small programs stored in the blockchain that are executed automatically when certain conditions are met. Because the blockchain is decentralized, these programs are executed simultaneously within each participant in the chain. When it comes to how these are used in detail, blockchains have diverged, sometimes a fair bit. But this concept opens up gigantic possibilities for applications.

U.S. startup Open Health Platform has launched Patient-Sphere, a data-sharing platform that uses blockchain technology to give patients control over their health data for research, in exchange for payment. What do you think of this development?
Technically, we're already there. When I started as an assistant chairman 20 years ago, we already had projects with hospitals on digital patient records. Today, we're still basically at the same point, because we haven't been able to solve some problems yet –  and that's where blockchain comes in. One of the big hurdles is identity management.

What do you mean by that?
If you store crap on a blockchain, it remains crap. Participants in a blockchain don't suddenly become trustworthy just by participating. I could make myself an infinite number of accounts and in the end, they're just pseudonyms. So, especially with things as sensitive as medical records, I first have to build digital trust and then, use the strengths of the blockchain.

So in the healthcare sector, you need not only blockchain as part of the solution, but also ...
...digital identity management. We couldn't implement that 20 years ago because, for example, we didn't have mobile devices yet. The idea now is that in the future you will have an "ID wallet" on your smartphone in which, for example, your ID card, driver's license and credit card are stored. This wallet has a public ID that can be stored on the blockchain. But it can only be opened and read with a personal password. In technical jargon, this is called "public-private key infrastructure" or a certificate-based approach. In the end, you have what are known as "self-sovereign identities," or SSIs for short.

How can the common folk envision that? 
Over the past few years, we have seen that the previous methods have reached their limits primarily with the fact that  we use different passwords for all areas; we constantly have to log in everywhere time and time again. The eCommerce sector has addressed the problem by allowing you to log in uniformly with your Facebook or Google account, for example. But then you blindly trust a platform that tracks all your transactions. That's convenient, but problematic. It can still work in the consumer space, but it wouldn't be a solution at all for businesses. In the healthcare sector it would be completely unacceptable to hand over data to third parties. Data sovereignty means that I retain control over the data.

How does a blockchain help there now?
The blockchain would be the layer where you find the reference to the issuer of the proof. So you can query bilaterally and check whether an identity is genuine - just like the Bundesdruckerei (Germany’s federal producer of documents and devices for secure identification, ed.note)guarantees that for ID cards today. Certificates can be checked there, so that the authenticity of your proof is confirmed in the ID wallet. So, here’s the deal: If you can manage your identity with such certificates, then you can do the same with all your data. So, you can then control what data insurance companies or doctors are generally allowed to see from you. Companies can now create a whole new ecosystem around this idea.

Why can't that be done without blockchain?
Blockchain creates a layer on which you put references or data itself. It's like a database that everyone can access with equal rights. But I don't have to trust any third party to run that database. You see this today with cryptocurrencies, whose transactions are stored on the blockchain. No one can change data there, and everything is visible and traceable.

Providers like BEAT advertise storing health and fitness data on a blockchain platform. The benefits the company communicates include: Motivation for sports via cryptocurrency, coordinated employee health, and monetization of one's own health data. Do you even need a blockchain for something like that?
Here we have a critical aspect, namely storing data on a blockchain. If a provider stores its customers' data on such a proprietary blockchain, then technically that is not far removed from a conventional database. However, that is not the purpose of a blockchain. It would be faster and cheaper with normal database technology.

Today, I can already collect more and more health data myself via technical gadgets, from blood pressure to blood sugar to sleep quality. How will this change the work of family doctors?
In principle, a doctor today only ever performs individual examinations, because he only ever has the data from one patient at a time. But if he had the data from many patients, he could make completely different evaluations. For example, if my doctor has my sleep data, he could then compare it with the data of millions of other patients around the world, if these patients have released their data for such analyses. This would also allow for the strengths of human doctors and artificial intelligence – which use "federated machine learning" to make diagnoses –to be combined. One example from cancer research: studies show that doctors currently miss spotting tumors more often, while AI triggers false alarms too often. So in combination with a doctor, such an AI can be pretty darn good, in any case much better than the actual situation.

So let’s say that if I go to the doctor with high blood pressure, he could look at which therapies have had what success rate with other people in their mid-forties in Central Europe with high blood pressure?
Exactly – and this access to other patients' data is in real time. So your doctor only sees the data of patients who have released their data at that exact moment. With a simple flu, such a mass evaluation is not absolutely necessary. But it would be very valuable for cancer diagnoses, and in a pandemic, such methods would also be extremely important. Google was quick to derive flu waves based on searches –but then, there's just that problem again of one provider "owning" all the data.

Where will blockchain technology stand in the healthcare sector in five years?
Should we be able to build good identity management and use blockchain more and more for such purposes, it will fade more and more into the background. Perhaps we will then call all the services that are built on it “Web 3.0”, or name them after a network that becomes established worldwide.
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