Understanding the Protein in Grains
When assessing the protein content of any food, it’s important to look beyond the total grams listed on a nutrition label. The quality, amino acid profile, and bioavailability are all critical factors. For grains, this often means understanding the concepts of complete versus incomplete proteins.
Complete vs. Incomplete Proteins
Proteins are made up of amino acids. Our bodies can produce 11 of the 20 necessary amino acids, but the other nine, known as essential amino acids (EAAs), must come from our diet. A "complete protein" source contains all nine EAAs in sufficient quantities. Animal products are typically complete proteins. Most grains, however, are considered "incomplete" because they are low in one or more essential amino acids, most notably lysine.
There are exceptions, with quinoa and amaranth being two prominent examples of grains that are complete protein sources. For most other grains, the deficiency in certain amino acids is not a problem for overall health, provided you eat a variety of different plant foods throughout the day, such as pairing grains with legumes. The outdated advice that you must combine complementary proteins in the same meal has been debunked; what matters is the variety over the course of a day.
The Bioavailability Factor
Another consideration is protein bioavailability, which is how well your body can digest, absorb, and utilize the protein from a food source. Plant-based proteins from grains tend to be less bioavailable than animal proteins. This is partly due to their fibrous structure and the presence of anti-nutrients like phytates, which can inhibit nutrient absorption. However, this is largely accounted for by dietary guidelines that recommend slightly higher protein intake for plant-based eaters to compensate for this difference. Choosing whole grains over refined grains also matters, as whole grains contain more nutrients, including more protein.
The Practical Answer: Yes, You Should Count Grain Protein
For most individuals, it is not only acceptable but recommended to count the protein from grains towards your daily total. The decision to count this protein depends on your overall dietary approach and health goals.
For Plant-Based Diets
For vegans and vegetarians, every source of protein counts. Since meat and dairy are excluded, plant-based foods, including grains, are crucial for meeting protein requirements. Being mindful of the amino acid profile and intentionally combining sources like beans and rice or hummus and pita over the course of the day is a smart strategy to ensure all EAAs are obtained. For those with higher protein needs, such as athletes, grains can be a critical part of the daily intake, often supplemented with more protein-dense plant foods or powders.
For Omnivorous Diets and Athletes
Even if you eat animal products, ignoring the protein from grains can lead to an underestimation of your total protein intake. Whole grains provide significant amounts of protein, and counting it helps create a more accurate nutritional picture. For athletes or individuals focused on muscle gain, every gram contributes. While animal proteins may be prioritized for their complete amino acid profile and high bioavailability, the protein from grains still provides valuable building blocks, carbohydrates for energy, and crucial micronutrients. In fact, one study showed that a whole-grain diet enhanced protein turnover and net protein balance compared to a refined-grain diet.
How to Optimize Protein from Grains
To maximize the protein benefits from grains, consider these strategies:
- Choose Whole Grains: Whole grains, such as quinoa, farro, and whole wheat, contain more protein and fiber than their refined counterparts.
- Combine with Legumes: The classic pairing of beans and rice is a perfect example of how to create a complete protein source by combining grains (low in lysine) with legumes (high in lysine).
- Add Nuts and Seeds: Topping oatmeal or a grain bowl with nuts and seeds, like almonds, walnuts, or pumpkin seeds, is an easy way to boost protein and healthy fats.
- Incorporate High-Protein Grains: Regularly include complete or high-protein grains like quinoa, amaranth, teff, and spelt in your meals.
- Don't Overlook Supplements: For those with very high protein needs, a plant-based protein powder made from sources like peas or soy can be a useful supplement.
High-Protein Grain Comparison
This table illustrates the protein content of various cooked whole grains per one-cup serving, according to USDA data.
| Grain | Protein per cooked cup (approx.) | Amino Acid Profile | Ideal Pairing for Complete Protein | Other Key Nutrients |
|---|---|---|---|---|
| Sorghum | 20 grams | Incomplete (low in lysine) | Legumes, nuts, seeds | Magnesium, iron, B vitamins, fiber |
| Farro | 12 grams | Incomplete (low in lysine) | Legumes, nuts, seeds, dairy | Fiber, iron, magnesium |
| Teff | 10 grams | Incomplete (low in lysine) | Legumes, nuts, seeds | Calcium, iron, fiber, B vitamins |
| Amaranth | 9 grams | Complete | No pairing needed | Iron, magnesium, phosphorus, fiber |
| Quinoa | 8 grams | Complete | No pairing needed | Fiber, folate, magnesium, zinc, iron |
| Wild Rice | 6.5 grams | Incomplete (low in lysine) | Legumes, nuts, seeds, dairy | Manganese, phosphorus, zinc, fiber |
| Oats | 6 grams | Incomplete (low in lysine, threonine) | Peanut butter, nuts, seeds | Fiber (beta-glucan), antioxidants, magnesium |
Potential Downsides and Considerations
While counting grain protein is beneficial, it's important to keep context in mind. Some people with very high protein needs or certain health conditions may need to focus more on highly bioavailable, complete protein sources. Additionally, a reliance on refined grains for protein can lead to a diet high in carbohydrates with fewer overall nutritional benefits. Always prioritize whole, minimally processed foods.
Conclusion: Every Gram Counts
Yes, you absolutely should count protein from grains. Whether you are following a plant-based diet or are an omnivore, counting this protein provides a more accurate nutritional assessment. While most grains offer incomplete proteins, a varied diet that includes legumes, nuts, and seeds throughout the day effectively supplies all essential amino acids. Furthermore, grains provide essential fiber, vitamins, and minerals that contribute to overall health. Incorporating a variety of whole grains into your meals is an effective and nutritious way to support your daily protein goals and overall well-being. For a simple and effective strategy, consider the classic complementary pairings or choose a complete grain like quinoa.
References
For further information on the nutritional value of grains and protein metabolism, consult these sources:
