The egg diet is a short-term, low-carbohydrate eating plan that uses eggs as the primary source of protein and fat, typically lasting anywhere from three days to two weeks. Most versions resemble a stripped-down Atkins-style approach: high protein, very low carbs, and limited food variety. The appeal is rapid weight loss, but the trade-offs are significant.
How the Egg Diet Works
The core idea is simple: eggs are filling relative to their calorie count, so building meals around them naturally reduces how much you eat overall. A single large egg has about 70 calories, 6 grams of protein, and 5 grams of fat, with virtually zero carbohydrates. When you eat several eggs a day alongside a small list of approved foods, your total calorie intake drops sharply.
There’s real science behind the satiety piece. A crossover study in overweight and obese adults found that eating eggs for breakfast led to significantly less hunger and lower calorie intake at lunch compared to a cereal breakfast. The egg breakfast provided 25 grams of protein versus 11 grams from cereal, and even though the cereal meal was higher in fiber, it didn’t compensate. Participants reported feeling fuller, more satisfied, and like they could eat less after the egg-based meal. Protein is the most satiating of the three macronutrients, and eggs deliver it in a compact, low-calorie package.
Eggs also appear to influence appetite hormones. Evidence suggests they help suppress hunger signals while boosting hormones that promote fullness. Combined with the very low carbohydrate intake, most versions of the diet push your body toward burning stored fat for energy, similar to ketosis.
Common Versions of the Diet
There isn’t one single egg diet. Several variations circulate online, and they differ in strictness and duration.
The 14-day boiled egg diet is the most widely known. It typically allows boiled eggs at every meal alongside lean proteins like chicken or fish, non-starchy vegetables, and small amounts of fruit. Bread, pasta, sugar, and processed foods are eliminated. It functions like a standard low-carb diet that happens to feature eggs prominently.
The egg fast is far more restrictive. Originally developed as a three-to-five-day protocol for people stalling on ketogenic diets, it comes with a rigid set of rules:
- Minimum six whole eggs per day, yolks included
- One tablespoon of butter or fat per egg consumed
- Up to one ounce of full-fat cheese per egg
- Eat within 30 minutes of waking, then every three to five hours
- Eat even if you’re not hungry
- Stop eating three hours before bed
This version is essentially eggs, butter, and cheese for days on end. It’s designed to be temporary, not a long-term eating plan.
A third variation, sometimes called the “egg-only” diet, restricts food to just eggs and water. This is the most extreme and least nutritionally sound version.
What the Weight Loss Actually Looks Like
People following these plans often report losing several pounds in the first week. Most of that initial drop is water weight. When you cut carbohydrates dramatically, your body burns through its stored glycogen, and each gram of glycogen holds roughly three grams of water. The scale moves quickly, but the underlying fat loss is much smaller.
A systematic review and meta-analysis of clinical trials found that egg consumption can increase short-term satiety and may be effective in controlling weight and reducing BMI, though researchers noted the mechanism isn’t fully understood beyond the protein content. The key phrase is “short-term.” No large clinical trials have tested eating six-plus eggs daily for weeks at a time as a dedicated weight loss strategy. The evidence supports eggs as a useful part of a balanced diet, not as a foundation for an entire eating plan.
Regaining lost weight after returning to normal eating is common with any highly restrictive short-term diet, and the egg diet is no exception. The calorie deficit that drives the loss disappears the moment you go back to your usual meals.
Side Effects and Nutritional Gaps
Eating this way for even a few days can produce noticeable side effects. Low-carbohydrate diets commonly cause constipation, fatigue, headaches, and bad breath. The constipation comes from reduced fiber intake, since most high-fiber foods (whole grains, beans, many fruits) are off-limits. The fatigue and headaches are your body adjusting to running on less glucose.
The bigger concern is nutritional balance. Eggs are nutrient-dense, but they don’t contain everything your body needs. They’re low in vitamin C, fiber, and certain minerals. Eating only one or two foods for days creates gaps that, while manageable over a long weekend, become more problematic over a full two-week stretch. The more restrictive the version, the faster those gaps add up.
Cholesterol and Heart Health
Eating six or more eggs a day raises an obvious question about cholesterol. A single large egg contains about 186 milligrams of dietary cholesterol, nearly all of it in the yolk. On the egg fast, you could easily consume over 1,100 milligrams daily.
The relationship between dietary cholesterol and heart disease is more nuanced than it once seemed. The 2015 Dietary Guidelines Advisory Committee stated that cholesterol intake “need not be limited” because the link between dietary cholesterol and blood cholesterol levels is weak, and that eggs should be considered part of a healthy diet. However, an updated meta-analysis involving over 3.6 million participants found that consuming one additional egg per day was associated with a small but statistically significant increase in cardiovascular disease risk. The pooled relative risk was 1.04, meaning a 4% increase per extra daily egg.
For most healthy people, a temporary spike in egg consumption over three to five days is unlikely to cause lasting harm. But if you have existing high cholesterol, a family history of heart disease, or diabetes, the calculus changes. The longstanding guideline of capping dietary cholesterol at 300 milligrams per day still reflects the cautious position of many cardiologists.
Who This Diet Is (and Isn’t) For
The egg diet is a crash diet. It can produce quick results on the scale, which makes it appealing before an event or as a psychological reset for people who feel stuck. The three-to-five-day egg fast was specifically designed for that purpose: breaking through a weight loss plateau on a ketogenic diet, not serving as a standalone program.
It’s a poor fit for anyone looking for sustainable weight loss, people with a history of disordered eating, or anyone with cholesterol-related health concerns. The restrictive nature makes it difficult to follow for more than a few days without fatigue, food monotony, and the side effects of very low carbohydrate intake wearing you down.
If eggs appeal to you as a weight management tool, the research supports a less dramatic approach: eating eggs as a high-protein breakfast to naturally reduce how much you eat later in the day. That strategy has clinical backing, no rigid rules, and none of the risks that come with eating almost nothing else.