Purple Diet vs Ultra-processed Diet for Obesity

(ULTRA PIlot Trial)

This trial tests two types of diets—the Purple Diet and an ultra-processed diet—to assess their effects on obesity-related health outcomes. The study aims to determine the feasibility of enrolling and following participants while collecting data for a larger future trial. Participants will alternate between the two diets over two weeks, allowing researchers to evaluate the health impacts of each diet. Ideal candidates are individuals who have been dealing with being overweight or obese and are willing to adhere to the assigned diet plans. As an unphased trial, this study offers participants the chance to contribute to groundbreaking research on diet and obesity.

The trial does not specify if you need to stop taking your current medications. However, if you are on medications that affect weight or diabetes outcomes, you must have been on a stable dose for at least 3 months to participate.

Previous studies on the Purple Diet, which includes foods rich in purple pigments, have shown potential benefits for weight management and health. Research suggests that purple foods might help lower cholesterol and control weight gain. For example, in a study where neither participants nor researchers knew who received the purple food product, participants reported feeling slightly less hungry after consuming it. This suggests the diet is generally well-tolerated and may positively affect weight.

Researchers are excited about these dietary approaches for obesity because they explore the impact of food processing levels on weight management. The Ultra-processed Diet examines foods that make up a significant part of many people's diets, such as soft drinks and packaged snacks, which are often linked to weight gain. On the other hand, the Purple Diet, despite being high in saturated fat and sugars, provides a comparison to typical American eating habits, which can offer insights into realistic dietary modifications. Unlike traditional weight loss treatments focusing on medications or surgical interventions, this trial could reshape how we understand dietary influences on obesity by highlighting the effects of food processing.

This trial will compare the effects of a Purple Diet with an Ultra-processed Diet on obesity. Studies have shown that consuming large amounts of ultra-processed foods (UPF) is linked to weight gain and a higher risk of obesity. One study found that people gained about 2 pounds on a UPF diet, while they lost weight on a diet with less processed foods. In contrast, purple foods, which contain natural pigments called anthocyanins, may aid in weight loss and improve cholesterol levels in people with obesity. Animal studies suggest these pigments can reduce body fat and cholesterol. While both diets are being tested in this trial, current evidence indicates that ultra-processed foods may cause weight gain, whereas purple foods might assist with weight loss.¹²⁶⁷⁸