How Many Carbs Are in 6 Raw Oysters? A Complete Nutritional Breakdown

November 10, 2025 •

4 min read

According to nutritional data, a typical serving of 6 medium raw oysters contains approximately 5 grams of carbohydrates. This places them firmly in the low-carb category, making them a suitable option for those following ketogenic, paleo, and other carb-controlled diets.

Quick Summary

This guide details the precise carbohydrate content of 6 raw oysters, explores the reasons for their carbohydrate load, and highlights their rich nutritional profile and health benefits.

Key Points

Low Carbohydrate Count: 6 raw oysters contain approximately 5 grams of carbohydrates, making them ideal for low-carb diets.
Source of Carbs: The carbs in oysters come from glycogen, the animal's stored energy source.
Nutrient-Dense: Oysters are rich in zinc, Vitamin B12, iron, and omega-3 fatty acids, offering significant health benefits.
Keto-Friendly: The low carb content means oysters can be safely included in a ketogenic diet without exceeding daily carb limits.
Preparation Matters: To keep the dish low-carb, stick to raw preparations with low-sugar sauces, and avoid breading.
Variation Exists: The exact carb count can vary slightly based on the oyster species and size, but remains consistently low.
Heart Health: The omega-3s in oysters support cardiovascular health and help manage cholesterol.

The Carbohydrate Content of 6 Raw Oysters

The carbohydrate count for six medium-sized raw oysters is generally low, averaging around 5 grams. However, it is important to note that this number can vary depending on the exact size, species, and nutritional database referenced. For example, some data points from the USDA suggest a slightly lower figure, with 6 medium wild eastern oysters containing closer to 2.3 grams of total carbohydrates. This variation is normal and reflects the natural differences found in wild-caught seafood. Regardless of the minor discrepancy, oysters remain a very low-carb food, far from the carb-heavy fare many associate with a standard diet.

Why Do Oysters Have Carbohydrates?

The presence of carbohydrates in shellfish like oysters often surprises people who assume all seafood is carb-free. The carbs in oysters come primarily from glycogen, which is essentially the animal’s form of stored energy. Unlike muscle tissue in mammals, which depletes most of its glycogen after death, oysters can retain some of this energy reserve. The amount of glycogen can also fluctuate throughout the year, with oysters harvested in colder months sometimes having a higher glycogen content as they store energy for reproduction.

Oysters: More Than Just a Low-Carb Treat

While their low-carb count is a major selling point for those on specific diets, the true value of oysters lies in their extraordinary nutritional profile. They are packed with essential vitamins and minerals that support overall health.

A serving of six medium raw oysters typically provides:

High-quality protein: Approximately 6 grams, offering a building block for muscle and tissue repair.
Zinc: Often exceeding the daily recommended intake, zinc is vital for immune function, wound healing, and mood stability.
Vitamin B12: A single serving can provide over 100% of your daily needs, supporting nerve function and red blood cell formation.
Iron: Excellent for preventing iron deficiency anemia and carrying oxygen throughout the body.
Omega-3 Fatty Acids: Heart-healthy fats that reduce inflammation and support brain function.
Selenium and Copper: Important trace minerals that act as powerful antioxidants.

Low-Carb Seafood Comparison

To put the carbohydrate content of oysters into context, here is a comparison with other popular low-carb seafood options. Values are based on 6 medium oysters or an equivalent 3-ounce serving size, and are approximate based on various sources.


Seafood Type	Serving Size	Approximate Carbohydrates	Notes
Raw Oysters	6 medium	2.3g - 5g	Glycogen contributes to carb content.
Shrimp	3 oz, raw	<1g	Virtually carb-free; a staple in many low-carb diets.
Salmon	3 oz, raw	0g	High in omega-3s and completely carb-free.
Tuna	3 oz, raw	0g	Also a zero-carb fish option.
Crab Meat	3 oz, raw	<1g	Very low carb, but may have trace amounts.

Serving Oysters on a Low-Carb Diet

For those adhering to a low-carb lifestyle, preparing raw oysters is key to keeping the carb count down. The traditional way of serving them on the half-shell with a squeeze of lemon or a dash of hot sauce is perfectly low-carb. However, care must be taken with accompaniments.

Avoid high-carb sauces: Many mignonettes and cocktail sauces are loaded with sugar. Opt for a simple lemon juice and vinegar dressing or a specific low-carb hot sauce.
Stick to raw: Cooking methods like frying or baking often involve breading, which adds significant carbohydrates. Enjoying them raw is the best way to control your intake.
Simple is best: Pair raw oysters with other low-carb sides, like a simple green salad, to create a balanced meal without hidden carbs. For more recipe ideas, you can explore low-carb cookbooks or websites, but always cross-reference the nutritional information. For example, some recipes might call for breading, so it is important to modify it to fit your dietary needs, such as using a low-carb alternative.

Conclusion: A Smart Addition to Your Low-Carb Meal Plan

In summary, the number of carbs in 6 raw oysters is minimal, making them a fantastic addition to almost any low-carb or ketogenic diet. Their carbohydrate content, sourced from natural glycogen, is insignificant when weighed against their incredible density of essential micronutrients like zinc, Vitamin B12, and omega-3 fatty acids. By choosing simple, low-carb preparations, you can enjoy these delicious shellfish while staying on track with your health and dietary goals.

How to Find and Select Fresh Oysters

Trust your senses: Fresh oysters should have a clean, oceanic smell. An off or fishy odor is a red flag.
Check the shell: A live, fresh oyster will have a tightly closed shell. If it's open, give it a tap. If it doesn't close, discard it.
Know your source: Purchase from a reputable seafood market or a restaurant with high turnover. This ensures freshness and proper handling.
Store correctly: Keep oysters in the refrigerator, flat side up, and cover them with a damp cloth. Never store them in standing fresh water.
Enjoy immediately: For the best taste and safety, consume raw oysters as soon as possible after purchase.
Link to an Authority Source: Healthline has an excellent article on oyster nutrition.

Frequently Asked Questions

Yes, oysters are an excellent choice for a keto diet due to their low carbohydrate and high nutrient content. A typical serving of 6 raw oysters contains very few carbs, which easily fits within a daily keto macro budget.

Cooking methods like frying or baking with breading will significantly increase the carbohydrate count. However, simply steaming or grilling oysters will not substantially change the carb count from their raw state.

Yes, you can eat a moderate number of oysters, as they are very low in calories and fat while being high in protein. Just remember to account for the few grams of carbohydrates per serving to ensure you stay within your daily limit.

Yes, all oysters and some other shellfish like octopus and mussels contain some carbohydrates due to their glycogen stores. The exact amount varies by species and size.

The carbohydrates in oysters come from glycogen, which is a polysaccharide that acts as the animal’s main energy storage.

Yes, many types of fish, such as salmon, tuna, and tilapia, contain zero carbohydrates. Most shrimp and crab are also virtually carb-free.

The healthiest and lowest-carb way to eat oysters is raw, on the half-shell, with a squeeze of fresh lemon juice, a dash of hot sauce, or a simple mignonette made without added sugar.