Eating more raw vegetables may help weight loss, reduce heart disease risk

• Researchers have found a link between plant-based diets and better long-term health outcomes, particularly related to obesity.
• The study indicated that a plant-based diet may be effective for controlling weight and improving diet quality to prevent and manage metabolic disorders.
• The study, in particular, demonstrates that eating more raw vegetables can have a significant impact on health.

Researchers from Qilu Hospital of Shandong University conducted a review that shows a link between plant-based diets and better long-term health outcomes, particularly related to obesity.

The research highlights that a plant-based diet offers an effective approach to weight control and enhancing diet quality to prevent and manage metabolic disorders.

While full veganism may not be necessary, the study demonstrates that simply eating more vegetables can have a significant impact on health outcomes.

Their analysis, published in Frontiers in Nutrition , adds to the evidence linking plant-based diets to improved long-term health, related to weight loss and heart disease prevention.

Research consistently shows that vegetarian and vegan diets are associated with better cholesterol levels, heart and brain health, digestive function, immune system strength, and overall longevity.

This doesn’t mean everyone should immediately eliminate meat from their diet, but it suggests that reducing meat consumption where possible can significantly impact health.

Benefits of plant-based diets tend to increase over time

The research team reviewed 24 studies on plant-based diets and weight loss, analyzing data from 2,223 individuals aged 18 to 82, with diet durations ranging from two to 96 weeks, and found that the benefits of plant-based diets tend to increase over time.

While participants following strictly vegan diets experienced the greatest weight loss, it wasn’t much higher than those who still consumed dairy and eggs.

However, studies involving higher consumption of raw vegetables showed the strongest connection to reduced risks of obesity and heart disease.

Although randomized controlled trials can’t definitively prove that eating raw vegetables directly leads to better health, the researchers conducted a second analysis using Mendelian randomization, a method better suited to identifying cause-and-effect relationships in health.

The team identified genetic variants linked to factors like plant-based diets and vegetable consumption by analyzing genetic data from a public database.

This analysis suggested that eating more raw vegetables was more likely responsible for the weight loss observed, rather than genetic predisposition.

Raw vegetables contain anti-inflammatory compounds

The researchers note that raw vegetables contain compounds like phytosterols and unsaturated fats that help reduce blood cholesterol levels.

They also highlight substances such as tocopherols, ascorbate, carotenoids, saponins and flavonoids, which have anti-inflammatory and antioxidant effects.

While increasing raw vegetable intake can improve health, avoiding taking a fully raw plant-based approach too far is important, as this can result in nutrient deficiencies.

Therefore, the researchers’ key message from these studies is to focus on incorporating more vegetables into the diet, rather than adopting a strictly vegan lifestyle.

Two experts who were not involved in this research spoke to Medical News Today .

Haley Bishoff , RDN, LD, plant-based registered dietitian and owner of Rūtsu Nutrition in Las Vegas, said, “It’s promising that the discussion around plant-based eating is getting more popular.”

“In this research article, nothing was considered ‘causal’; however, a potential or correlative relationship between plant-based eating and positive health outcomes should be convincing enough,” Bishoff explained.

“Plant-based diets tend to be naturally lower in calories, higher in fiber and lower in saturated fats, which makes sense why a plant-based diet has shown to reduce the risk of high cholesterol, type 2 diabetes, hypertension, and obesity. If you’re looking to incorporate plant-based eating, it’s important to do so under the guidance of a registered dietitian to make sure that there are no nutrient gaps and individual health concerns are being considered.”
— Haley Bishoff

Courtney Pelitera , MS, RD, CNSC, registered dietitian specializing in sports nutrition and wellness nutrition, said, “this study is very interesting in that it is a Mendelian randomization study, which considers the genetic variants as exposure to help consider the outcomes.”

“It looked specifically at randomized control trials that compared plant-based diets to animal-based diets and weight loss. Studies were excluded if they included physical activity. This is definitely a topic that needs further research to be definitive on the outcomes of plant-based diets when associated with weight and ASCVD,” she said.

The inconsistencies appear to have been the biggest setback in this study due to differences in the evaluated papers,” Pelitera pointed out.

Benefits of increasing plant-based foods

Bishoff added that “people can greatly benefit from learning about the benefits of eating more plant-based. Plus, it can be an incredibly easy change to make.”

Is going vegan necessary?

“Remember that being plant-based doesn’t mean you have to be a strict vegan. Many people get turned away by the thought of that. Even a heart healthy, Mediterranean diet can be considered plant-based because a majority of the foods come from plant sources. The goal is really just to consume a majority of your foods from fruits, vegetables, legumes, whole grains, nuts, and seeds.”
— Haley Bishoff

“If you’re not sure how to put this into action, aim to eat 50% of your meals and snacks in produce form. Just by increasing fiber consumption alone, you can help fight inflammation, rid your body of waste, improve blood lipid levels and so much more,” Bishoff added.

Pelitera agreed, adding that “calorie restriction in diets results in overall weight loss (fasted or non-fasted).”

“Plant based diets will help with a reduction in body weight, likely due to increased filling fiber with increased vegetable intake and a reduction in overall energy intake. Increased raw vegetable consumption was also associated with lower BMI and risk of obesity. A plant based diet is shown to reduce and even reverse the risk of ASCVD mortality. It has positive effects on blood lipid levels, lowers blood pressure, and reduced the risk for type 2 diabetes.”
— Courtney Pelitera

“In short, we want to recommend increased vegetable intake in our patients in order to reduce body weight and reduce the risk of ASCVD,” Pelitera explained.

“If a patient is willing and interested in a plant-based diet, this should be discussed with the patient as an excellent option. The patient ideally would be coached through implementing the plant-based diet with a registered dietitian, especially if this is a major change in their life. This will help ensure all nutrient needs are being met while maintaining the diet,” she added.