What happens if I only eat beans and rice?

November 29, 2025 •

4 min read

While beans and rice combine to form a complete protein, a diet of only these two staples is not advised for long-term health and can lead to severe nutritional deficiencies over time. What happens if I only eat beans and rice is that you'll miss out on a wide spectrum of essential vitamins, minerals, and fats necessary for proper bodily function.

Quick Summary

An exclusive diet of beans and rice, while providing some protein and fiber, will inevitably lead to severe nutrient deficiencies. Long-term consumption risks major health problems due to the absence of crucial vitamins, minerals, and essential fats. Variety is essential for optimal health.

Key Points

Nutrient Deficiencies: An exclusive beans and rice diet is severely lacking in essential vitamins (A, C, D, E, K, B12) and minerals (calcium, iodine, zinc, iron), leading to potential deficiencies over time.
Complete Protein, Incomplete Nutrition: While together they form a complete protein, this does not mean the diet is nutritionally sound. It's only one component of a healthy diet.
Digestive Issues: The high fiber content, while beneficial in moderation, can cause significant gas, bloating, and other digestive discomforts when eaten exclusively.
Long-Term Health Risks: Sustaining this diet for extended periods increases the risk of chronic health problems, including osteoporosis, neurological damage, and Type II diabetes.
Budget-Friendly Fixes: Nutritional value can be greatly improved by adding inexpensive items like frozen vegetables, fruits, healthy oils, and varying the types of grains and beans.
Supplementation is Key: Those on a plant-based diet heavily reliant on beans and rice will need to consider supplementation for vital nutrients like Vitamin B12.

The Initial Benefits and The Inevitable Downside

For many cultures and individuals on a budget, beans and rice are a dietary staple. Their affordability and ease of preparation, combined with the fact that they form a complete protein when eaten together, make them an appealing option for survival or saving money. This means they contain all nine essential amino acids that the human body cannot produce on its own. However, the story doesn't end there. A complete protein is just one piece of the complex puzzle of human nutrition. The severe lack of other crucial micronutrients and fats in this limited diet presents significant risks over the long term.

Unavoidable Nutritional Deficiencies

Eating only beans and rice, even with varieties like brown rice, will leave you with a long list of missing nutrients. The primary deficiencies that develop on such a diet include:

Vitamins A, C, D, E, and K: These essential vitamins are almost entirely absent. For example, Vitamin C deficiency can lead to scurvy over time, a serious condition characterized by fatigue, swollen gums, and poor wound healing.
Vitamin B12: Primarily found in animal products, this vitamin is completely missing from a strict bean and rice diet. A B12 deficiency can cause anemia, neurological issues, and irreversible nerve damage if left untreated.
Essential Fatty Acids (Omega-3s): The body needs fats for brain health, hormone production, and inflammation regulation. An exclusive bean and rice diet contains minimal fat, leading to a deficiency in omega-3s, which are vital for heart and brain health.
Calcium: Crucial for bone health, calcium intake would be far below recommended levels, increasing the risk of osteoporosis over time.
Iodine: This mineral is often lacking in plant-based diets unless fortified salt is used. Deficiencies can lead to thyroid problems.
Zinc and Iron: While present in beans, the bioavailability (how well the body absorbs them) is lower than from animal sources. A sustained diet without diverse sources could lead to deficiencies.

The Health Consequences of Dietary Monotony

Beyond specific deficiencies, a beans and rice-only diet can cause a range of other health problems, many of which are related to the sheer monotony and lack of diversity.

Digestive Issues

The very high fiber content of beans, while beneficial in a balanced diet, can cause digestive discomfort when consumed exclusively and in high quantities. An abrupt increase can lead to gas, bloating, stomach cramps, diarrhea, or even constipation if fluid intake isn't sufficient. In extreme cases, and for individuals with pre-existing conditions, it could even risk bowel obstruction.

Blood Sugar Regulation

If white rice is the primary grain, its high glycemic index can lead to frequent spikes in blood sugar, which is particularly concerning for those at risk of or with Type II diabetes. While brown rice is a healthier option, it is not a complete solution for regulating blood sugar over the long term without other food groups.

Psychological Impact

Eating the same two foods day after day can have a significant psychological impact. The lack of variety can lead to food boredom, depression, and a loss of enjoyment in eating, which is a key component of a healthy lifestyle.

How to Build a Better Beans and Rice Diet

For those on a tight budget, adding a few inexpensive items can drastically improve the nutritional profile of a beans and rice diet. A balanced diet should include a wide range of food groups, as detailed by health organizations like the NHS.

Add vegetables and fruits: Incorporate whatever is seasonal and affordable. Even frozen vegetables are a cost-effective way to get Vitamins A, C, and K. A handful of spinach or carrots can significantly boost Vitamin A, while a side of citrus fruit provides Vitamin C.
Include healthy fats: Add some avocado, olive oil, or a sprinkle of flaxseed or chia seeds to your meal to increase essential fatty acid intake.
Switch to brown rice: Opting for brown rice over white rice adds more fiber and minerals like magnesium, potassium, and zinc.
Vary the legumes: Don't stick to just one type of bean. Rotate between lentils, chickpeas, and various other beans to vary nutrient profiles. You can learn more about the nutritional value of legumes from sources like MD Anderson Cancer Center.
Consider fortification and supplements: For nutrients like Vitamin B12, fortification (e.g., fortified plant-based milk or nutritional yeast) or supplementation is often necessary for those avoiding animal products.

Diet Comparison: Beans and Rice Only vs. Varied Diet


Feature	Beans and Rice Only Diet	Varied, Balanced Diet
Protein Quality	Complete when combined.	All essential amino acids from diverse sources like meat, eggs, beans, and grains.
Fiber Content	Very high, potentially causing digestive issues.	Adequate and balanced, promoting regular digestion.
Vitamin Profile	Deficient in Vitamins A, C, D, E, K, and B12.	Rich in a full spectrum of vitamins from diverse fruits, vegetables, and other foods.
Mineral Profile	Low absorption of iron and zinc; deficient in calcium and iodine.	Adequate absorption of a wide range of minerals.
Essential Fats	Lacking in crucial omega-3 fatty acids.	Includes healthy fats from nuts, seeds, oils, and other sources.
Long-Term Impact	High risk of chronic health problems and malnutrition.	Promotes sustained wellness and reduces disease risk.

Conclusion

While a diet of beans and rice can offer sustenance and a complete protein in a pinch, relying solely on this combination is a recipe for long-term health decline. The significant nutrient deficiencies and potential for digestive distress outweigh the benefits of affordability and simplicity. To achieve true health, especially over the long haul, it is imperative to diversify your diet with vegetables, fruits, and healthy fats. Even with limited resources, small additions can make a monumental difference in preventing malnutrition and securing overall wellness. The message is clear: man cannot live on rice and beans alone.

Frequently Asked Questions

Yes, for a very short period, you can survive on beans and rice. However, for a week or two, it would not lead to an immediate crisis, but it is not recommended for optimal health. Long-term health requires a much more varied diet.

This diet is deficient in essential Vitamins A, C, D, E, K, and B12. Key minerals like calcium and iodine are also missing, and the absorption of iron and zinc is often poor.

While switching to brown rice is an improvement over white rice, providing more fiber, magnesium, potassium, and zinc, it does not solve the wider nutritional deficiencies found in this restricted diet.

Eating too many beans, especially without a gradual increase, can lead to uncomfortable digestive issues such as gas, bloating, cramps, and changes in bowel habits due to the high fiber content.

You can significantly improve the meal by adding affordable vegetables (fresh or frozen), fruits, and a source of healthy fat like olive oil or avocado. Varying the types of beans and grains also helps.

While the high fiber content can help you feel full longer and the meal is relatively low in calories, it is not a sustainable or healthy weight loss diet due to the severe nutrient deficiencies it causes.

No, your body can combine the amino acids from different foods eaten throughout the day. It is not necessary to pair beans and rice in the same meal to achieve a complete protein.