How Does the Nova Diet Work? Understanding the Food Classification System

According to research published in The BMJ, a high intake of ultra-processed foods has been linked to increased risk for over 30 adverse health outcomes, including heart disease and cancer. The NOVA diet, more accurately a dietary framework based on the NOVA classification system, offers a powerful alternative by categorizing foods by their level of processing and encouraging a shift toward more natural eating.

Quick Summary

The Nova diet is a dietary approach that uses the NOVA system, a four-tiered food classification model based on processing level, to guide healthier food choices toward less-processed options. It focuses on whole foods and minimizes industrially created, ultra-processed products.

Key Points

• NOVA is a Classification System: The 'Nova diet' refers to a dietary approach based on the NOVA system, which categorizes foods by their level of processing, not their nutrient content.

• Embrace Unprocessed Foods: The core principle is to base your diet on Group 1 foods—unprocessed or minimally processed items like fresh fruits, vegetables, whole grains, and lean proteins.

• Minimize Ultra-Processed Intake: The diet advocates avoiding or severely limiting Group 4 ultra-processed foods, which are industrial products high in sugar, fat, salt, and additives.

• Prioritize Food Quality Over Calories: This approach focuses on the quality and source of your calories, not just the quantity, recognizing that your body processes whole foods differently.

• Reduces Health Risks: Adopting a NOVA-inspired diet can lower the risk of obesity, cardiovascular disease, type 2 diabetes, and other chronic illnesses by cutting down on unhealthy industrial additives.

• Check the Ingredients: A good rule of thumb for identifying ultra-processed foods is to look for a long list of unfamiliar ingredients not typically used in home cooking.

What is the NOVA Food Classification System?

Developed by Brazilian researchers, the NOVA food classification is a system for grouping foods based on the extent and purpose of their processing. Unlike other dietary systems, NOVA focuses on how food is made, providing a practical framework for identifying beneficial foods. This system has influenced dietary guidelines and research globally on the link between processing and health.

The Four NOVA Food Groups

Group 1: Unprocessed and Minimally Processed Foods

These are foods in their natural state or minimally altered without added salt, sugar, or unhealthy fats. They form the basis of a healthy diet in the NOVA framework.

Examples:

• Fruits and vegetables (fresh, frozen, dried)
• Whole grains, legumes
• Meat, fish, eggs
• Milk, plain yogurt
• Water, fresh juices (unsweetened)

Group 2: Processed Culinary Ingredients

Derived from Group 1 foods or nature, these are used sparingly for cooking and seasoning.

Examples:

• Oils, butter
• Salt, sugar, honey
• Vinegar

Group 3: Processed Foods

Made by adding Group 2 ingredients to Group 1 foods for preservation or flavor enhancement, these typically have few ingredients and are recognizable. They should be eaten in moderation.

Examples:

• Canned vegetables, salted nuts
• Cheeses
• Fresh bread (unwrapped)
• Canned fish

Group 4: Ultra-Processed Foods

Industrial products made from extracted substances with numerous additives to improve flavor, color, texture, and shelf life. They contain minimal or no intact Group 1 food and are designed to be convenient and highly palatable. The NOVA approach recommends avoiding these.

Examples:

• Packaged snacks, soda, most breakfast cereals
• Ready-to-eat meals, processed meats
• Margarine

How the Nova Dietary Approach Works

The NOVA-based diet is a shift toward prioritizing fresh and minimally processed foods (Group 1), using Group 2 ingredients moderately, and avoiding ultra-processed products (Group 4). This approach naturally leads to a diet higher in beneficial nutrients like fiber, vitamins, and minerals, while reducing intake of harmful components common in ultra-processed foods. Studies show a link between minimally processed diets and improved health outcomes, including weight loss. Focusing on whole foods encourages home cooking and healthier habits.

NOVA Approach vs. Nutrient-Based Diets

Feature	NOVA-Based Approach	Nutrient-Based Diets (e.g., Calorie Counting)
Primary Focus	Extent of food processing.	Nutrient content.
Food Quality	Prioritizes whole, minimally processed foods and minimizes ultra-processed foods.	Doesn't distinguish processing level if nutrient targets are met.
Dietary Advice	Avoid ultra-processed products; build meals with whole ingredients.	Focus on macro/micronutrient targets, portion sizes, and calorie limits.
Mechanism for Results	Increased beneficial nutrients, reduced harmful additives.	Primarily creating a caloric deficit.
Long-Term Adherence	Encourages lifestyle changes and cooking habits.	Can feel restrictive; focuses on numbers over food quality.

Health Benefits of a NOVA-Inspired Diet

Reducing ultra-processed food intake by adopting a NOVA-inspired diet offers significant health benefits, backed by research linking UPF consumption to various diseases.

Key benefits include:

• Improved Weight Management: High UPF intake is linked to obesity; the NOVA approach aids satiety and calorie control.
• Better Cardiovascular Health: Lowering UPF reduces exposure to excess sodium, unhealthy fats, and is associated with reduced cardiovascular risk.
• Reduced Risk of Diabetes: Lower UPF intake, coupled with higher fiber from whole foods, helps regulate blood sugar and reduces type 2 diabetes risk.
• Enhanced Mental Health: Lower UPF intake is linked to reduced risk of anxiety and depression.
• Better Gut Health: Whole foods provide fiber beneficial for the gut microbiome, while additives in UPFs can be detrimental.

Conclusion: Adopting a Healthier Processing Perspective

The NOVA system provides a valuable framework for choosing healthier foods based on processing level. By emphasizing unprocessed foods and limiting ultra-processed items, it offers a sustainable path to better health and well-being. Prioritizing foods close to their natural state helps in making informed decisions about diet quality.

For further details on the principles, refer to the Brazilian dietary guidelines, which align with the NOVA framework.

Frequently Asked Questions

What is the primary difference between a Nova-based diet and other diets?

Unlike traditional diets that focus on counting calories or macronutrients, a Nova-based diet primarily focuses on the level of food processing. It encourages prioritizing whole, minimally processed foods over ultra-processed options.

How do I know if a food is ultra-processed?

Ultra-processed foods typically contain five or more ingredients, including industrial additives not commonly used in home cooking, and often contain high levels of added sugar, fat, and salt. They are designed for convenience and have a long shelf life.

Are all processed foods bad on the NOVA diet?

No. The NOVA system has four categories. Minimally processed foods (Group 1) are the foundation of the diet, while processed culinary ingredients (Group 2) and simply processed foods (Group 3) are acceptable in moderation. The focus is on avoiding ultra-processed foods (Group 4).

Can I lose weight by following a NOVA-based diet?

Yes, studies have shown that prioritizing minimally processed foods can lead to greater weight loss and reduced cravings compared to a diet of ultra-processed foods, even when calorie intake is similar.

Does the NOVA diet require me to cook all my meals from scratch?

While cooking from scratch is highly encouraged, the Nova diet is not an all-or-nothing approach. It's about making conscious choices to reduce your reliance on ultra-processed options. Small changes, like swapping packaged snacks for fruit and nuts, make a big difference.

What are some easy switches to make toward a NOVA-based diet?

Swap sweetened yogurt for plain yogurt, packaged breakfast cereals for rolled oats, instant noodles for brown rice or quinoa, and packaged snacks for fresh fruit or nuts.

Is the NOVA diet healthy for my gut and mental health?

Yes. The emphasis on whole foods naturally increases fiber intake, which benefits the gut microbiome. Additionally, a lower intake of ultra-processed foods is associated with better mental health outcomes, including a lower risk of anxiety and depression.