Experts' Honest Opinions on the Sardine Diet for Weight Loss

Sardines are experiencing a surge in popularity. Once considered a pantry staple for emergencies, theyve now become trendy, with social media creators experimenting with the so-called sardine diet. Curious whether this fish-focused regimen actually supports weight loss? We consulted nutrition and medical experts to clarify.

What the Sardine Diet Entails

The sardine diet involves consuming mostly sardines. It gained attention in 2023 thanks to Dr. Annette Bosworth, who promoted a short three-day challenge featuring only sardines, water, and black coffee. Seasonings or carb-free sauces can be added for flavor. Some social media users have attempted longer periods on this restrictive plan, reporting dramatic weight loss, such as one individual claiming to shed 25 pounds in 120 days on sardines alone.

Does It Actually Promote Weight Loss?

Experts caution against relying on this diet for sustainable weight loss. Dr. Hector Perez, a bariatric surgeon, explains that while eating only sardines might reduce calories due to monotony, it represents undereating rather than a healthy approach. Such single-food diets often result in short-term weight loss but can cause nutrient deficiencies or binge eating once the diet ends.

Registered dietitian Monica Auslander Moreno adds that a lack of dietary variety can lead to electrolyte imbalances and dangerous nutrient deficiencies.

Nutritional Profile of Sardines

A 3.75 oz serving of sardines canned in water provides approximately:

• 90 calories
• 22.6 grams of protein
• 351 mg of calcium
• 2 grams of fat
• 343% DV of vitamin B12
• 22% DV of vitamin D
• 15% DV of iron

If canned in oil, sardines contain around 190 calories and 10.5 grams of fat. They are also rich in zinc, magnesium, and omega-3 fatty acids, which support heart, brain, eye health, and reduce inflammation.

Health Benefits of Sardines

Although experts discourage an all-sardine diet, sardines can be a valuable addition to a balanced diet. Moreno notes their low mercury levels, affordability, ease of preparation, high protein content, and omega-3 richness, which support immunity, cognition, and anti-inflammatory benefits. Sardines with bones also provide highly absorbable calcium and vitamin D, which are important for bone health.

Risks of a Sardine-Only Diet

Sardines are low in fiber, which is essential for metabolism and gut health. Perez warns that exclusive consumption can lead to high sodium intake and nutrient imbalances, negatively affecting digestion and metabolism. Dr. Rasoul Montazeri emphasizes that people with hypertension, kidney issues, heart failure, gout, or sodium sensitivity should avoid this diet, as it can worsen blood pressure, strain kidney function, and trigger inflammation. Pregnant individuals and those with metabolic disorders also require a more balanced nutrient intake. Additionally, sardines with bones may pose a choking hazard, and anyone with fish allergies should avoid the diet entirely.

Conclusion

While the sardine diet may result in short-term weight loss, it is not recommended for long-term results or overall health. A well-rounded approach, such as the Mediterranean diet, DASH diet, or intermittent fasting, is more effective for sustainable weight loss. Sardines can complement these diets, providing valuable nutrients without becoming the sole food source.

Author: Noah Whitman