What are the Two Types of Grains? A Comprehensive Guide

December 25, 2025 •

3 min read

According to the American Heart Association, whole grains can help lower your risk of heart disease and stroke. This nutritional advantage underscores the key difference between the two types of grains: whole and refined. Whole grains contain all parts of the kernel, while refined grains have had the bran and germ removed during milling.

Quick Summary

This guide explains the fundamental differences between whole and refined grains, detailing their distinct nutritional profiles, processing methods, and impacts on health. It provides examples, benefits, and practical advice for incorporating more whole grains into your diet for better health outcomes.

Key Points

Two Grain Types: Grains are classified into two main types: whole grains and refined grains.
Whole Grain Anatomy: Whole grains consist of the bran, germ, and endosperm, retaining all their original nutrients.
Refined Grain Processing: Refined grains have the bran and germ removed during milling, which strips them of fiber and many essential vitamins.
Nutrient Differences: Whole grains offer more fiber, B vitamins, minerals, and antioxidants compared to refined grains.
Enrichment vs. Wholeness: While some refined grains are 'enriched' with nutrients, they still lack the fiber and full nutrient profile of whole grains.
Health Benefits: Prioritizing whole grains is linked to a reduced risk of heart disease, stroke, and type 2 diabetes due to their fiber content and other nutrients.
Make Wise Swaps: Simple dietary changes, like choosing brown rice over white, can significantly increase whole grain intake.

Understanding the Anatomy of a Grain

Before diving into the two types of grains, it's essential to understand the basic structure of a single grain kernel. Every grain is composed of three primary, edible parts:

The Bran: The hard outer layer rich in fiber, B vitamins, and minerals.
The Germ: The nutrient-rich embryo containing B vitamins, vitamin E, healthy fats, and antioxidants.
The Endosperm: The largest part, providing starchy carbohydrates, protein, and some B vitamins.

The Two Types of Grains: Whole and Refined

Whole Grains: The Nutritional Powerhouse

Whole grains include all three parts of the kernel. This minimal processing preserves their natural fiber, vitamins, minerals, and antioxidants, offering health benefits like improved digestion, better heart health, and reduced risk of chronic diseases such as type 2 diabetes.

Examples of Whole Grains:

Brown Rice
Oats
Quinoa
Barley
Whole Wheat
Millet

Refined Grains: The Polished Option

Refined grains are milled to remove the bran and germ, leaving only the endosperm. This results in a finer texture and longer shelf life but removes significant fiber, B vitamins, and iron. While often enriched with some nutrients, they do not regain their original levels, and fiber is not replaced.

Examples of Refined Grains:

White Rice
White Flour
White Pasta
Crackers and Cookies made with refined flour

Comparison: Whole Grains vs. Refined Grains


Feature	Whole Grains	Refined Grains
Processing	Minimally processed, retains all kernel parts.	Milled to remove bran and germ.
Kernel Parts	Contains bran, germ, and endosperm.	Contains only the endosperm.
Nutrient Density	High in fiber, vitamins, minerals, antioxidants.	Lower in nutrients.
Enrichment	Naturally nutrient-rich.	Often enriched, but fiber is not replaced.
Shelf Life	Shorter.	Longer.
Texture	Heartier, chewier.	Finer, softer.
Health Impact	Reduced risk of heart disease, stroke, type 2 diabetes.	Can contribute to blood sugar spikes.

How to Incorporate More Whole Grains

Increasing whole grain intake can significantly improve your diet. Simple tips include replacing white rice and pasta with brown and whole-wheat versions, trying diverse grains like quinoa or farro, starting the day with oatmeal, checking labels for "whole grain" or "100% whole wheat" as the first ingredient, and using whole-grain flours in baking. Avoid products just colored brown.

The Role of Processing in Grain Nutrition

Processing itself isn't always detrimental. Milling, for instance, is necessary to make flour. The key difference is that whole-grain processing retains all kernel parts, preserving nutrients, while refining specifically removes the nutrient-dense bran and germ. Refined grain processing leads to reduced nutritional value, whereas processed whole-grain items like whole-wheat bread still offer good nutritional benefits.

Conclusion

Understanding the difference between the two types of grains—whole and refined—is crucial for making healthy dietary choices. Whole grains, with all kernel parts intact, provide essential fiber, vitamins, and minerals that support health and reduce chronic disease risk. Refined grains, stripped of bran and germ, lose many beneficial nutrients. Even when enriched, refined grains lack the full nutritional profile of whole grains. Prioritizing whole grains is a simple step towards a healthier lifestyle.

For more information on whole grains, you can visit The Whole Grains Council.

Frequently Asked Questions

The primary difference lies in their composition. Whole grains contain the entire kernel—the bran, germ, and endosperm. Refined grains have had the bran and germ removed through processing, leaving only the starchy endosperm.

No, not all processed grain is refined grain. While milling grains into flour is a form of processing, whole-grain products are made by keeping all parts of the kernel intact. Refining is a specific type of processing that removes the most nutrient-dense parts.

Fiber is a key component found in abundance in whole grains, specifically the bran. It aids in digestion, helps lower cholesterol, and contributes to a feeling of fullness. Refined grains lose almost all their fiber during processing.

No. While enriched refined grains have some B vitamins and iron added back after processing, they still lack the significant amount of fiber and other essential nutrients found naturally in whole grains.

To identify whole-grain products, always check the ingredients list. The word 'whole' should appear before the grain's name (e.g., 'whole wheat flour') and be listed as one of the first few ingredients.

No. Color can be deceiving. Some bread and food manufacturers use additives like molasses or caramel coloring to make refined grain products appear darker, mimicking the look of whole grains.

In specific medical cases, yes. For individuals with certain gastrointestinal conditions like Inflammatory Bowel Disease (IBD) or gastritis, doctors may recommend a low-fiber diet that includes refined grains, as they can be easier to digest.

Common whole grains include brown rice, oats, quinoa, and whole-wheat bread. Common refined grains include white rice, white bread, white pasta, and crackers made from white flour.