Which food has more protein and iron?

January 14, 2026 •

3 min read

Iron deficiency is the most common nutritional deficiency worldwide, affecting up to one-third of the global population. Knowing which food has more protein and iron is key for addressing deficiencies and maintaining energy levels, muscle health, and overall well-being.

Quick Summary

This guide reveals the best sources for protein and iron from both animal and plant-based foods. It details iron absorption differences and compares key nutritional information to help you make informed dietary decisions.

Key Points

Heme vs. Non-Heme Iron: Animal products contain heme iron, which is significantly more easily absorbed by the body than the non-heme iron found in plants.
Animal Superstars: Shellfish like oysters and clams, along with red and organ meats, are the most concentrated sources of both high-quality protein and highly bioavailable heme iron.
Plant-Based Powerhouses: Legumes (lentils, chickpeas), seeds (pumpkin, sesame), and soy products (tofu) are excellent sources of both plant-based protein and non-heme iron.
Maximize Plant Iron: To increase the absorption of non-heme iron from plant sources, consume them alongside a food high in Vitamin C, such as bell peppers or tomatoes.
Balanced Diet is Key: The most effective way to ensure adequate intake is to combine a variety of animal and plant-based protein and iron sources in your diet.
Absorption is Critical: The raw amount of iron in a food doesn't tell the whole story; its bioavailability is a more important factor for your body's utilization.
Cooking Matters: Using a cast iron skillet can increase the iron content of your food, providing an extra boost, especially for those on a vegetarian diet.

Understanding Protein, Iron, and Bioavailability

Protein is an essential macronutrient vital for building and repairing tissues, producing hormones and enzymes, and supporting immune function. Iron is a crucial mineral needed to produce hemoglobin, which carries oxygen in the blood, and its deficiency can lead to fatigue and anemia.

Not all iron is created equal. The body absorbs iron from food in two forms: heme and non-heme.

Heme iron: Found exclusively in animal products like meat, poultry, and seafood. It is more readily absorbed by the body, with an absorption rate of 15% to 35%.
Non-heme iron: Found in plant-based foods, such as vegetables, legumes, nuts, and fortified products. Its absorption rate is lower, typically between 2% and 10%.

Factors Affecting Iron Absorption

Certain dietary factors can inhibit or enhance your body's ability to absorb iron from non-heme sources.

Enhancers: Pairing non-heme iron foods with those rich in Vitamin C (like bell peppers, citrus fruits, and tomatoes) significantly boosts absorption. Cooking with a cast iron pan can also add a small amount of iron to your meals.
Inhibitors: Compounds such as phytates (in grains and legumes), calcium (in dairy), and polyphenols (in tea and coffee) can reduce iron absorption when consumed together.

Top Animal-Based Food Sources

Animal products are renowned for their high-quality, complete protein and superior heme iron content. Some of the most potent sources include:

Shellfish: Clams, oysters, and mussels are exceptionally rich in both protein and iron. Oysters, in particular, pack a significant iron punch, while clams are noted for their high iron density per serving.
Red Meat: Lean red meats, including beef, lamb, and venison, are excellent sources of both protein and heme iron. A 3-ounce serving of lean beef can provide over 24 grams of protein along with highly bioavailable iron.
Organ Meats: Offal like beef and chicken liver is extremely rich in iron. A 3-ounce serving of beef liver contains a very high concentration of iron.
Poultry: The dark meat of chicken and turkey contains more iron than the white meat, while still offering high-quality protein.

Top Plant-Based Food Sources

For those following a vegetarian or vegan diet, a variety of plant foods offer substantial amounts of protein and non-heme iron. Combining these strategically can help meet daily needs.

Legumes: Lentils, chickpeas, and beans are fantastic sources of plant-based protein and iron. Cooked lentils provide a significant amount of both nutrients per cup.
Seeds: Pumpkin seeds, sesame seeds, and flaxseeds are packed with protein, iron, and healthy fats. Pumpkin seeds, especially, offer a notable iron content.
Soy Products: Tofu and tempeh are derived from soybeans and are considered complete proteins, making them valuable staples in plant-based diets.
Dark Leafy Greens: Spinach, Swiss chard, and kale contain non-heme iron. To maximize absorption, pair them with a Vitamin C source like lemon juice.
Whole Grains: Quinoa is a complete protein that provides a good amount of iron and fiber. Other whole grains like amaranth and spelt also contribute significantly.

Comparison of Key Protein and Iron Sources


Food (per 100g serving)	Type of Iron	Approximate Protein Content (g)	Approximate Iron Content (mg)
Cooked Lentils	Non-heme	~9	~3.3
Lean Beef	Heme	~25	~2.5
Oysters	Heme	~10	~8.3
Tofu (extra firm)	Non-heme	~17	~2.7
Pumpkin Seeds	Non-heme	~30	~8.5
Cooked Spinach	Non-heme	~3	~2.7
Dried Apricots	Non-heme	~3.4	~2.7

Note: Nutritional values can vary based on preparation and brand.

Conclusion: Which Food Has More Protein and Iron?

Ultimately, no single food reigns supreme across the board for both protein and iron. Animal sources, especially shellfish, red meat, and organ meats, tend to offer both higher concentrations and better bioavailability of iron compared to most plant-based options. However, plant-based foods are excellent choices, especially when consumed strategically with Vitamin C-rich foods to enhance absorption.

For a balanced diet, combining both animal and plant-based foods is ideal. For instance, a meal of lean beef and spinach offers both heme and non-heme iron, with the animal protein aiding overall absorption. Vegetarians and vegans can ensure sufficient intake by eating a varied diet of legumes, seeds, and fortified grains and focusing on Vitamin C pairing. The best strategy is to consume a variety of protein foods to meet both macro and micronutrient requirements, as outlined by organizations like the USDA. The key to optimizing your intake of both protein and iron lies in a diverse, thoughtful diet tailored to your nutritional needs and preferences.

MyPlate.gov

Frequently Asked Questions

Heme iron is derived from animal hemoglobin and is easily absorbed by the body. Non-heme iron is found in plants and is less efficiently absorbed, with absorption rates significantly lower than heme iron.

Yes, because the iron in plant foods (non-heme iron) is less bioavailable, those on a plant-based diet typically need about 80% more iron to meet their requirements compared to those who eat meat.

Fruits are not typically high in protein, but some dried fruits like apricots and raisins, along with mulberries, contain notable amounts of non-heme iron. For better absorption, pair them with Vitamin C-rich fruits like strawberries or citrus.

The most effective method is to pair non-heme iron foods with a source of Vitamin C. For example, add bell peppers to a lentil soup or lemon juice to a spinach salad.

Yes, canned clams are an excellent source of heme iron. A 3-ounce serving can provide a very high amount of iron, making them one of the most iron-dense seafood options available.

Yes, especially with acidic foods cooked in it for longer periods. Small amounts of dietary iron can leach into your food from a cast iron pan, which is a helpful boost for your intake.

Symptoms of protein deficiency can include brittle hair and nails, fatigue, and muscle weakness. Iron deficiency can cause extreme tiredness, pale skin, shortness of breath, and headaches.