The recent public appearance of Zomato CEO Deepinder Goyal wearing a small metallic device on his temple has ignited a fierce debate in India's health-tech and medical circles. Promoted as an experimental wearable called 'Temple' that monitors cerebral blood flow in real-time, the device has been met with sharp criticism from leading neurologists who question its scientific validity and medical utility.
The Device and the Controversy
During a podcast, Goyal described the Temple device as a tool to understand brain health by tracking blood flow. This initiative is linked to his new research foundation, which advocates the Gravity Ageing Hypothesis. This hypothesis proposes that gravity's constant pull on blood circulation in the brain forces it to work harder, leading to faster ageing and wear.
The device quickly became a topic of intense speculation on social media. However, the conversation turned critical when a former AIIMS radiologist dismissed it as a "fancy toy for billionaires" with "no scientific standing." This sparked a wider discussion on the need for rigorous validation of consumer health wearables before they are presented as credible medical tools.
Medical Experts Voice Strong Skepticism
Leading neurologists have raised fundamental questions about the device's claimed capabilities. Dr. Praveen Gupta, a prominent neurologist and Chairman of Marengo Asia International Institute of Neuro and Spine (MAIINS) in Gurugram, provided a detailed rebuttal.
He explained that a single-point external device cannot reliably measure blood flow across the entire brain. "The brain has many arteries with different blood flow patterns. A device attached at one point cannot reliably measure blood flow across both sides of the brain or across all arteries, especially the deeper and smaller ones," Dr. Gupta stated.
He emphasized the complexity of brain physiology, which involves billions of neurons and intricate vascular networks. Measuring a signal from one external location cannot capture this complexity or accurately reflect what is happening deep inside the brain tissue.
Can It Diagnose Cognitive Decline? The Answer is No
A core claim implied by such wearables is the ability to gauge brain health or risk of degeneration. Experts firmly debunk this. "Brain diseases are extremely complex... Measuring blood flow at one location cannot explain cognition decline or neurodegeneration," Dr. Gupta clarified.
He provided a crucial example: some individuals can function normally even with a complete blockage in one artery because other vessels compensate. This demonstrates that localized blood flow measurements are medically insufficient for assessing overall brain health. Significant disease-related changes in blood flow occur over years, not days or weeks, requiring long-term studies, not snapshot readings from a wearable.
Established Medical Tools vs. Unvalidated Wearables
The medical community already uses validated, proven technologies to assess cerebral blood flow when clinically necessary, such as in cases of stroke or transient ischemic attacks. These include:
- Angiography (CT, MR, or conventional)
- Transcranial Doppler ultrasound
- Other specialized imaging modalities
In contrast, the Temple device "lacks a clear scientific hypothesis, robust foundation, and validated data," according to the expert critique. Proper medical research for such a device would require a clear hypothesis, experimental validation, and long-term longitudinal studies to see if any measured data correlates with actual health outcomes.
The episode underscores a critical gap in the booming health-tech industry: the tension between innovative ambition and the non-negotiable need for scientific rigor. It serves as a cautionary tale for consumers and investors alike to scrutinize the medical claims of direct-to-consumer health devices before accepting them as tools for wellness or diagnosis.
