What Will Happen if I Only Eat Meat and Eggs?

According to the U.S. Dietary Guidelines, an exclusive meat and egg diet eliminates entire food groups, making it nutritionally incomplete. If you only eat meat and eggs, your body will experience significant and potentially dangerous changes, ranging from digestive issues and nutrient deficiencies to cardiovascular and kidney strain.

Quick Summary

A meat and egg-only diet leads to serious nutrient deficiencies, causing digestive problems from lack of fiber, increased heart disease risk, and stress on the kidneys and liver.

Key Points

• Nutrient Deficiencies: An exclusive diet of meat and eggs lacks fiber, vitamin C, and antioxidants, leading to nutritional deficiencies over time.

• Digestive Issues: The complete absence of dietary fiber can cause significant digestive problems, including constipation or, for some, diarrhea.

• Increased Disease Risk: High intake of saturated fat from meat can raise LDL cholesterol, increasing the risk of heart disease and potentially colon cancer.

• Kidney and Liver Stress: Excessive protein consumption places a heavy burden on the kidneys and liver, potentially leading to long-term damage or kidney stones.

• Unsustainable Long-Term: This highly restrictive diet is difficult to maintain and lacks the variety needed for a sustainable, balanced, and enjoyable eating pattern.

Short-Term Effects: The Initial Adjustment Period

When transitioning to a diet consisting of only meat and eggs, the body undergoes a rapid and often noticeable adjustment. Within the first few weeks, many people experience initial side effects, both positive and negative. On the plus side, cutting out carbohydrates forces the body into a state of ketosis, where it burns stored fat for energy instead of glucose. This can lead to a quick reduction in water weight and a decrease in bloating and gas for some individuals. The high-protein, high-fat content also promotes a strong sense of satiety, which can lead to reduced overall calorie intake and weight loss.

However, the elimination of all plant-based foods triggers a number of short-term downsides as well. The lack of dietary fiber, exclusively found in plants, can cause constipation, a common initial complaint. Conversely, some individuals experience diarrhea due to the shift in their gut microbiome from a high-fat diet. Other transitional symptoms may include headaches, nausea, low energy, and "keto flu" as the body adapts to using fat as its primary fuel source. These symptoms are temporary for most but serve as a warning sign of the extreme dietary shift.

Long-Term Health Consequences

While short-term results may seem promising to some, the long-term health consequences of an exclusive meat and egg diet are a major concern for medical professionals.

Nutrient Deficiencies

The most significant issue is the elimination of vital nutrients found only in plant foods. Without fruits, vegetables, grains, and legumes, the body loses access to essential vitamins, minerals, antioxidants, and phytonutrients. This leads to deficiencies in:

• Vitamin C: Necessary for immune function and tissue repair. Its absence can lead to scurvy over time.
• Fiber: Critical for digestive health, cholesterol regulation, and gut microbiome diversity.
• Vitamins K and E: Important for blood clotting, bone health, and acting as antioxidants.
• Phytonutrients and Antioxidants: Plant compounds that fight inflammation and protect against chronic diseases.

Cardiovascular Risks

The carnivore diet typically involves a high intake of saturated fats and cholesterol, particularly from red and processed meats. This can increase levels of LDL ("bad") cholesterol, a well-established risk factor for heart disease. While some proponents argue against this link, the American Heart Association and other health bodies continue to recommend limiting red meat for cardiovascular protection. The lack of soluble fiber, which helps bind and remove cholesterol from the body, further exacerbates this risk.

Kidney and Liver Strain

The high-protein load of an all-meat diet places significant stress on the kidneys and liver. The liver must work harder to convert excess nitrogen from protein into urea, which the kidneys then filter out. Over time, this increased burden can lead to long-term organ stress, increased risk of kidney stones, and potentially impaired kidney function, especially in those with pre-existing conditions.

Gut Microbiome and Digestive Health

The gut microbiome thrives on dietary fiber, which is completely absent in a meat and egg-only diet. This drastically alters the bacterial composition in the gut, reducing diversity and potentially compromising the intestinal lining. A healthy gut microbiome is crucial for immunity, digestion, and even mental health. Research shows that diets rich in fiber, like the Mediterranean diet, are linked to better mood and lower depression risk, benefits that are lost on a carnivore-style diet.

Comparison: Meat & Eggs Only vs. Balanced Diet

Feature	Exclusive Meat & Egg Diet	Standard Balanced Diet (e.g., MyPlate)
Carbohydrates	Absent	Present in whole grains, fruits, vegetables, & legumes
Fiber	Absent; high risk of constipation/diarrhea	Ample; supports gut health and regular bowel movements
Key Vitamins	High in B12, Iron, Zinc; Deficient in C, K, E, Folate	Balanced intake of vitamins from diverse food groups
Heart Health	High saturated fat and cholesterol; potentially increased LDL	Controlled saturated fat; ample fiber to lower LDL
Kidney Health	High protein load places stress on kidneys	Moderate, manageable protein intake
Gut Microbiome	Decreased diversity due to fiber elimination	Diverse and healthy due to various prebiotics
Sustainability	Restrictive and difficult to maintain long-term	Flexible and sustainable for long-term health

The Verdict on Restrictive Diets

The carnivore diet, or any diet exclusively focused on meat and eggs, is an extreme and restrictive eating plan. While some individuals report short-term benefits like weight loss and reduced inflammation, these results are largely anecdotal and not supported by robust, long-term clinical trials. The elimination of entire food groups results in significant nutrient deficiencies, which can lead to a cascade of negative health consequences over time, including increased risk of heart disease, kidney issues, and colon cancer.

Health professionals and dietitians overwhelmingly advise against such restrictive eating patterns. Instead, they recommend a balanced diet rich in a variety of whole foods, including fruits, vegetables, whole grains, lean proteins, and healthy fats. This approach ensures all nutritional needs are met in a sustainable and health-promoting way. Individuals considering the carnivore diet or similar plans should consult a doctor or registered dietitian to understand the full scope of risks and explore healthier, more balanced alternatives.

Conclusion

Consuming only meat and eggs forces the body into a state of metabolic stress while creating severe nutrient deficiencies. The lack of fiber, vitamin C, and other essential compounds can lead to digestive problems, compromised gut health, and a heightened risk of serious conditions like heart disease and kidney stones. Although some may experience initial weight loss, this restrictive diet is not sustainable and poses significant, unproven long-term risks. A varied diet remains the gold standard for promoting overall health and wellness, offering a breadth of nutrients that an all-meat-and-egg diet cannot provide.

Frequently Asked Questions

Is it safe to eat only meat and eggs?

No, it is not considered safe or healthy long-term to eat only meat and eggs. This restrictive diet leads to severe nutrient deficiencies, lack of fiber, and an increased risk of heart disease and kidney problems due to high saturated fat and protein intake.

Will I lose weight if I only eat meat and eggs?

You may experience initial weight loss on this diet, primarily due to water weight loss from carbohydrate restriction and increased satiety from high protein intake. However, this weight loss is often not sustainable or healthy long-term and comes with significant health risks.

What happens to your gut on an all-meat and egg diet?

The gut microbiome suffers significantly from the complete lack of dietary fiber, leading to a reduction in bacterial diversity. This can cause digestive problems like constipation and may have negative long-term effects on immune function and overall health.

What nutrients are missing from a diet of only meat and eggs?

A diet consisting only of meat and eggs is deficient in key nutrients like Vitamin C, fiber, antioxidants, and various phytonutrients found in plants. While meat and eggs provide iron and B12, they cannot replace the full spectrum of vitamins and minerals.

Does eating only meat and eggs affect cholesterol?

Yes, a diet high in saturated fat and cholesterol, found in many meats and eggs, can raise LDL ('bad') cholesterol levels, increasing the risk of heart disease. The absence of fiber further hinders the body's natural ability to manage cholesterol.

Can an all-meat diet harm your kidneys?

Yes, the high protein load from an all-meat diet can put added stress on the kidneys. This may increase the risk of kidney stones and impair long-term kidney function, especially for individuals with pre-existing kidney disease.

What is a healthier alternative to a meat and egg only diet?

A healthier alternative is a balanced diet that includes a variety of whole foods from all food groups, such as the Mediterranean diet. This approach incorporates fruits, vegetables, whole grains, and lean proteins to ensure adequate nutrition and long-term health.