On New Year’s Day of 2024, a new show began streaming on Netflix, and while it seemed like an ordinary documentary, it soon began to grab the attention of people worldwide. The show took a different approach from what you might have seen in these kinds of documentaries - a scientific study, to be more specific.

You Are What You Eat: A Twin Experiment is a documentary where Christopher D. Gardner from Stanford University gives us a deeper view of how our dietary choices affect us. Based on a research experiment, the show give us a glimpse of what goes on in our bodies based on what we eat.

The show follows a set of 22 twins as part of an eight-week study. Each pair of twins is given separate diet plans. The idea was to see exactly what certain dietary habits do to the body - and it’s not just something that gave the participants a new perspective on health, but also viewers.

The show uses a DEXA machine to get a more scientific, data-driven perspective on the impact of these dietary choices. You Are What You Eat brought the DEXA scan under the spotlight, and now a lot of people are interesting in experimenting with these scans themselves.

Why Netflix Documentary “You Are What You Eat” used the DEXA Scan

For more than a hundred years, we’ve relied on BMI as a marker of health. When your BMI is higher than 25, you’re overweight. If it goes above 30, then you’re considered to be obese. Recently, scientists and medical experts have started to notice that BMI isn’t really the most accurate way of understanding a person’s health. That’s exactly where the DEXA scan comes into the picture.

There are two primary elements that you need to consider when analyzing your body mass: fat and muscle. A high amount of fat increases your risk of diseases. It’s thought that focusing on building muscle mass (while reducing fat mass) can help to lower these risks. In You Are What You Eat, DEXA is used to evaluate the participants. The TV show refrained from using the traditional BMI metrics, and rather wanted to give participants a more accurate and scientific approach to how dietary habits affect them.  

While the DEXA scan is often used to get a better idea of bone mass and the risk of osteoporosis, it offers a lot more data that medical experts can work with. It can be used to learn more about your lean mass, visceral fat, how fat is distributed throughout your body, and detect imbalances in your muscles. The potential and the level of data that DEXA scans offer are the main reasons why the documentary decided to use this technology.

How the DEXA Scan Helped Study Participants

The DEXA scan gave the participants valuable data to help them see exactly what certain foods do to their body composition. For example, did a vegan diet cause loss of muscle mass? This point has caused a heated debate among viewers. Perhaps, the best conclusion is that everyone is different, and the best way to know if to experiment.

DEXA was also able to offer more details than just telling the participants about their fat mass and muscle mass - it went into greater detail. For example, with the use of this technology, these participants were able to determine how much visceral fat they had. This is the fat that collects in your abdomen, and it can have an impact on your organs. Visceral fat is often also considered to be the most dangerous and raises the risk of health conditions much more than fat stored in other parts of the body.

How You Can Use the DEXA Scan to Run Your Own Experiments

After watching You Are What You Eat on Netflix, you might find yourself interested in trying DEXA technology yourself.

Should you change your diet? Should you increase protein intake? Should you run less and do more strength training exercises? Regardless of the experiment you’re looking to conduct, the DEXA Scan can give you much more details about your body compared to climbing onto a scale or measuring your BMI. With that in mind, here are a few tips:

1- Keep It Simple

One of the most useful lessons that self-experimentation enthusiasts tend to learn also happens to be the most basic. You will be tempted to do something complicated. Don’t. Do the simplest easiest thing that will tell you something. A simple experiment will go a long way.

2- Have a clearly defined goal

Looking to understand whether increased protein intake will help you build muscle mass? Make sure to structure your experiment around this specific question. By changing the quantity of your protein intake, you will be able to understand its impact on muscle mass. However, if you introduce too many questions in the same experiment, you might get lost in the data.

3- Do not introduce too many variables

If you change too many things in your lifestyle (e.g., nutrition, sleep, stress, supplements, and exercise), you might end up confused about what exactly led to the results of your DEXA Scan. Ideally, you want to have one or two variables in your experiment.

4- Collect before and after DEXA measurements

Find a location close to you that offers DEXA scans. You will want to use the same location for increased accuracy. You’ll usually get a full report after the scan. Aim for a follow-up scan two to three months after you start making changes. This will give you a chance to see, at a scientific level, how the changes you’ve made affected your body.

Looking for an example? See this 2017 experiment by our Co-founder and CEO Laila Zemrani “Training for Strength or Endurance?” Laila introduces changes in her exercise to better understand how different types of training influence body composition.