I’m making a protein shake every morning using raw eggs because I heard it’s a great way to get extra protein. However, my friend mentioned something about salmonella and other potential dangers associated with consuming uncooked eggs. I’m curious to know specifically: What are the real, tangible risks of eating raw eggs regularly, focusing on the potential health consequences, the likelihood of those consequences occurring (like how common is salmonella poisoning from raw eggs these days?), and what preventative measures, if any, can I take to minimize those risks if I want to continue including raw eggs in my diet?

Answer

The primary risks associated with eating raw eggs are Salmonella contamination and potential nutrient absorption issues.

Salmonella Contamination:

• Source: Salmonella bacteria can be present inside the egg itself or on the eggshell. Hens can be infected with Salmonella enteritidis, which can then contaminate the eggs before the shell is even formed.
• Symptoms: Salmonella infection (salmonellosis) typically causes diarrhea, fever, abdominal cramps, and vomiting, usually starting 12 to 72 hours after infection. Illness usually lasts 4 to 7 days, and most people recover without treatment.
• Severity: While most cases are mild, Salmonella infection can be severe, particularly in infants, young children, pregnant women, older adults, and people with weakened immune systems. In some cases, the infection can spread from the intestines to the bloodstream and then to other body sites, requiring hospitalization and antibiotic treatment. Rarely, untreated Salmonella infection can be fatal.
• Prevalence: The incidence of Salmonella in eggs varies depending on location and farming practices. Thorough cleaning and sanitation practices in commercial egg production have reduced the risk, but it’s not eliminated.
• Mitigation: Proper refrigeration of eggs can slow the growth of Salmonella. Cooking eggs thoroughly to an internal temperature of 160°F (71°C) kills the bacteria. Pasteurized eggs, which have been heated to kill bacteria, are a safer alternative for dishes that call for raw or lightly cooked eggs.

Nutrient Absorption Issues:

• Biotin Binding: Raw egg whites contain avidin, a protein that binds to biotin (vitamin B7). This binding can prevent the absorption of biotin in the small intestine, potentially leading to biotin deficiency if large quantities of raw egg whites are consumed regularly. Cooking denatures avidin, rendering it unable to bind to biotin, thus allowing for normal absorption. Egg yolks are a source of biotin, helping to counter the avidin in the white if the whole raw egg is consumed.
• Protein Digestibility: The proteins in raw eggs are not as easily digested as those in cooked eggs. Cooking denatures the proteins, making them more accessible to digestive enzymes. Studies have shown that the body can utilize significantly more protein from cooked eggs than from raw eggs.

Other Considerations:

• Cross-Contamination: Handling raw eggs can lead to cross-contamination of other foods and surfaces. It’s important to wash hands thoroughly with soap and water after handling raw eggs and to clean any surfaces that may have come into contact with them.
• Source of Eggs: Eggs from smaller farms or backyard flocks may not be subject to the same rigorous safety standards as those from large commercial operations. Knowing the source of your eggs and their handling practices can help you assess the risk.
• Individual Susceptibility: As mentioned, some individuals are at higher risk of complications from Salmonella infection. These individuals should avoid consuming raw or undercooked eggs altogether.

In summary, while the risk of contracting a Salmonella infection from eating raw eggs is relatively low, it is not zero. The potential for nutrient absorption issues is also a factor to consider, particularly with long-term consumption of raw egg whites. Cooking eggs thoroughly significantly reduces these risks.