Temple Brain Tracker: Doctors Question $900 Wearable’s Claims

Deepinder Goyal’s Temple wearable is facing scrutiny from Indian doctors over its claims of monitoring blood circulation to the brain, bringing scientific validation and regulatory oversight into focus for the growing health technology market.

The device, priced at 85,000 rupees (approximately $907), is designed to attach to the side of the head, between the forehead and ear. Its BrainFlow feature is promoted as a tool for monitoring changes in blood supply to the brain, while another metric, called Entropy, is intended to measure how hard the body works to regulate its internal temperature.

However, medical professionals have questioned whether the technology can reliably measure the physiological functions described in its promotional material. Critics argue that the device’s capabilities have not yet been established through sufficient peer-reviewed research.

Developed by Indian entrepreneur Deepinder Goyal, Temple has attracted attention through its association with prominent Indian sporting personalities, including cricket captain Shubman Gill and Olympic medallist P.V. Sindhu.

The disagreement has also raised a broader question for wearable technology companies: how should products be classified and regulated when fitness-monitoring features begin making claims about human health?

Why Indian doctors are questioning Temple’s BrainFlow technology

The main controversy centres on BrainFlow, Temple’s feature for tracking changes in blood circulation to the brain.

Medical professionals have questioned whether an optical sensor positioned against the skin near the temple can distinguish blood circulation within the brain from blood flow through superficial blood vessels.

Indian doctor Jason Philip told Reuters that optical signals collected from the skin in this location could provide information about the superficial temporal artery, which supplies blood to the face and scalp, rather than directly establishing cerebral blood flow.

Hepatologist Cyriac Philips, widely known as TheLiverDoc, has also criticised the device on social media. He has questioned the scientific basis of its health-related claims and called for greater public awareness about the limitations of wellness wearables.

Paediatrician and nephrologist Sanjeev Bagai has separately questioned the device’s regulatory status, describing it as a gimmick without formal approval or clearance.

The criticism reflects concerns about the distinction between collecting physiological signals and demonstrating that those measurements accurately represent a specific biological function.

Deepinder Goyal defends Temple as a fitness and wellness product

Goyal has rejected the criticism, maintaining that Temple is a fitness tracker and wellness product rather than a medical device.

The distinction is important because the company argues that the wearable is intended to provide information about physiological changes rather than function as a clinically approved diagnostic instrument.

Temple described BrainFlow and Entropy as metrics supported by emerging science. The company said further research would follow and acknowledged that certain features could eventually require regulatory approval.

The device is less than one inch wide and weighs under two grams. It is available in six colours and is positioned as a wearable that can monitor several physiological indicators, including thermal, immune, digestive, cognitive and emotional readings.

Despite the criticism, the company said it had received orders from customers in more than 62 countries, indicating commercial interest beyond its domestic market.

The reported order reach is an early indicator of international demand, although it does not establish the product’s clinical effectiveness or long-term commercial performance.

Temple’s $900 price raises the stakes for wearable technology

At 85,000 rupees, Temple occupies a premium position in the consumer wearable market.

Its pricing and positioning place greater importance on how clearly the company communicates the technology’s capabilities, limitations and intended applications.

For wearable manufacturers, the commercial opportunity lies in developing products that provide consumers with more detailed information about their physical condition. However, health-related claims can also create challenges when the underlying measurements have not been independently validated.

The distinction between a wellness metric and a clinically meaningful measurement is particularly relevant when devices claim to monitor functions associated with major organs.

For Temple, the central commercial challenge is establishing consumer confidence in its technology while addressing questions about the scientific evidence supporting its measurements.

Wearable technology companies face growing regulatory scrutiny

The debate surrounding Temple reflects a wider challenge for companies developing consumer health-monitoring products.

Wearable manufacturers increasingly incorporate sensors and software designed to provide information about blood pressure, heart activity and other physiological indicators. As these features become more closely associated with medical monitoring, regulators may examine whether they fall within medical-device requirements.

In the United States, the Food and Drug Administration (FDA) has already taken action involving wearable health-monitoring features.

In July 2025, the FDA issued a warning letter to wearable technology company WHOOP concerning its Blood Pressure Insights feature, stating that the product was being marketed without the required FDA marketing clearance or approval.

The FDA’s position illustrates how a feature marketed as part of a consumer wearable can attract medical-device scrutiny depending on its intended purpose and claims.

Apple has also introduced hypertension notifications for compatible Apple Watch models. The feature analyses patterns over a 30-day period and alerts users to possible hypertension, while Apple clarifies that it is not intended to diagnose or treat medical conditions.

These examples demonstrate the importance of distinguishing between wellness monitoring, health notifications and medical functions requiring regulatory authorisation.

What Temple means for India’s health technology sector

The controversy places Temple within a broader discussion about India’s ambitions in consumer technology and digital health innovation.

For companies developing wearable devices, the opportunity extends beyond conventional fitness tracking towards more sophisticated monitoring of physiological indicators.

However, commercial adoption will depend on more than product design, pricing and visibility. Scientific research, transparent performance data and appropriate regulatory compliance will also influence how consumers and healthcare professionals assess these products.

Temple’s reported orders from more than 62 countries suggest an international commercial footprint. Its longer-term position will depend on the company’s ability to substantiate its technology claims and communicate the intended use of its measurements.

For India’s emerging health technology businesses, the debate highlights the importance of balancing product innovation with scientific credibility.

Follow B2B Market Signal on social media for the latest business news, industry developments, market intelligence and analysis. Connect with us on LinkedIn and follow us on Instagram at @b2bmarketsignal for regular updates