**Sunscreen Shades: Dark Skin Bias in Boston Fitness Trackers**

By Franklin Everett Shaw

March 10, 2026

Are you trusting your fitness tracker a little too much? If you’re a person of color in the Boston area, the answer might be yes. Many popular wearables struggle to accurately measure heart rate and blood oxygen saturation (SpO2) on darker skin tones, potentially leading to skewed fitness data and even health risks.

This isn’t just a theoretical problem; it’s a real issue impacting Bostonians striving for optimal health. Let’s dive into why this happens and, more importantly, what you can do about it.

The science is clear: most optical sensors used in fitness trackers rely on photoplethysmography (PPG). This technology shines green light onto the skin and measures the amount of light reflected back to detect blood flow. Melanin, the pigment responsible for darker skin tones, absorbs more green light. This absorption can interfere with the sensor’s ability to accurately detect blood flow changes, leading to inaccurate readings.

Think about it: Boston’s diverse neighborhoods, from Roxbury to Dorchester, are filled with people who may be unknowingly affected by this technological bias.

So, what can you do? First, acknowledge the problem. Don’t blindly trust the data your tracker provides.

Next, research. Not all trackers are created equal. Some manufacturers are actively working to improve their algorithms to account for skin tone variations. Look for devices that have been independently tested and shown to perform well across diverse populations. Unfortunately, this information isn’t always readily available, requiring some digging.

Consider the Apple Watch. While not perfect, Apple has made strides in addressing skin tone bias in its heart rate and SpO2 sensors. Independent tests, though limited, suggest better accuracy compared to some competitors. However, always compare your readings with a pulse oximeter, especially during intense workouts.

Garmin is another popular brand. While they haven’t explicitly focused on skin tone in their marketing, some users with darker skin have reported acceptable accuracy with certain Garmin models. Again, independent verification is crucial.

Avoid relying solely on trackers from lesser-known brands, especially those with suspiciously low prices. These devices often lack the sophisticated algorithms and sensor technology needed for accurate readings across all skin tones.

Beyond choosing the right device, consider sensor placement. Experiment with wearing your tracker slightly higher on your wrist, where the skin may be thinner and less pigmented. Tighten the band to ensure good contact between the sensor and your skin.

Another biohack: try using a red light filter app on your phone while taking readings. While not a perfect solution, some users have reported improved accuracy by reducing the interference from green light. This is a DIY approach, so results may vary.

Boston’s altitude, though not extreme, can also affect SpO2 readings. At higher elevations, the partial pressure of oxygen in the air is lower, which can lead to lower SpO2 levels. This effect is amplified if your tracker is already struggling to accurately measure SpO2 due to skin tone.

The Boston climate also plays a role. Cold weather can constrict blood vessels, further complicating the sensor’s ability to detect blood flow. Ensure your wrist is warm before taking readings, especially during the winter months.

What about third-party apps? Some apps claim to improve the accuracy of wearable data by applying algorithms that correct for skin tone variations. However, be cautious. Many of these apps are unproven and may provide inaccurate or misleading information. Always consult with a healthcare professional before making any decisions based on data from these apps.

Here’s a step-by-step guide to reporting device bias:

1. Document the issue: Keep a record of inaccurate readings, noting the time, activity, and environmental conditions.
2. Contact the manufacturer: File a complaint with the device manufacturer, providing detailed information about the problem.
3. Report to the FDA: The Food and Drug Administration (FDA) regulates medical devices. You can report adverse events or device malfunctions through their MedWatch program.
4. File a complaint with the Massachusetts Attorney General’s Office: The Attorney General’s Office protects consumers from unfair and deceptive business practices.
5. Share your experience: Talk to your friends, family, and online communities about your experience. Raising awareness can help pressure manufacturers to address the issue.

Don’t underestimate the power of community. Connect with other fitness enthusiasts in Boston through local running clubs, gyms, or online forums. Share your experiences with different trackers and learn from others.

Consider joining or starting a local advocacy group focused on health equity in technology. This can be a powerful way to raise awareness and demand change from manufacturers.

Remember, your health data is valuable. Don’t let inaccurate readings from biased technology compromise your fitness goals. By being informed, proactive, and advocating for change, you can ensure that your fitness tracker provides accurate and reliable data, regardless of your skin tone.

The fight for equitable technology is ongoing. Your voice matters.