Almond milk is not a complete protein. It falls short on several essential amino acids, most notably lysine, and provides only about 1 gram of protein per cup. Even setting aside the quantity issue, the protein that is present in almond milk scores poorly on amino acid quality measures compared to cow’s milk or soy milk.
What Makes a Protein “Complete”
Your body needs 20 amino acids to build and repair tissue. It can manufacture 11 of them on its own, but the remaining nine must come from food. These nine, called essential amino acids, are histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine. A food qualifies as a complete protein only when it supplies adequate amounts of all nine.
Most animal proteins (meat, eggs, dairy) are complete. Among plant foods, soy and quinoa are the best-known complete sources. Nuts, grains, and legumes each tend to run low on at least one essential amino acid.
Where Almond Milk Falls Short
Lysine is the main problem. Research published in Food Science & Nutrition measured the amino acid scores of four commercial almond varieties and found lysine scores ranging from 0.49 to 0.56, meaning almonds deliver roughly half the lysine your body needs relative to the other amino acids present. That puts almonds in the same range as walnuts (0.51) and pecans (0.54), all limited by the same amino acid.
Lysine isn’t the only gap. When researchers tested almond-based beverages using a more advanced quality measure called DIAAS (digestible indispensable amino acid score), almond milk scored just 0.34 for lysine, 0.93 for threonine, and 0.94 for tryptophan. Any score below 1.0 means the food doesn’t deliver enough of that amino acid to meet requirements on its own. Almond milk falls below the threshold on three of seven amino acids tested, with lysine dramatically low.
The Bigger Problem: Very Little Protein Overall
Even if almond milk had a perfect amino acid profile, the total protein content is minimal. A standard cup of almond milk contains about 1 gram of protein. For comparison, a cup of cow’s milk has around 8 grams and soy milk provides roughly 7 grams. You would need to drink eight cups of almond milk just to match the protein in a single glass of dairy milk, and you’d still have an incomplete amino acid profile.
The reason for this gap is simple: commercial almond milk is mostly water. A typical carton contains only a small percentage of actual almonds. Whole almonds are a reasonable protein source at about 6 grams per ounce, but that concentration gets diluted dramatically during processing.
How Soy and Cow’s Milk Compare
Soy milk is the only widely available plant milk that matches dairy on protein quality. Every essential amino acid in soy milk scores above 100% on the DIAAS scale, with valine and tryptophan as the lowest at 111%. Cow’s milk scores even higher, with its lowest amino acid (tryptophan) still at 117%. Both are complete proteins by any standard measure.
Almond milk’s DIAAS profile tells a different story. Its lysine score of 34% is less than a third of what soy milk delivers for the same amino acid. Researchers have concluded that almond milk is not an adequate substitute for cow’s milk from a protein standpoint.
Pairing Almond Milk With Other Foods
If you prefer almond milk for taste, calories, or dietary reasons, you can fill in the amino acid gaps through other foods in the same meal or throughout the day. The key is adding lysine-rich foods, since that’s the amino acid almonds lack most. Legumes (beans, lentils, chickpeas) are high in lysine, making them a natural complement. Dairy products like yogurt also pair well with nuts to round out the amino acid profile.
Some practical combinations that create a complete amino acid set:
- Almond milk in a smoothie with soy protein or Greek yogurt, which covers the lysine gap directly
- Almond milk with oatmeal topped with chia seeds and a side of beans, combining grains and legumes
- Almond butter on whole grain bread with a glass of lentil soup, pairing nuts and grains with legumes
You don’t need to get all nine essential amino acids from a single food or even a single meal. Eating a varied diet over the course of a day takes care of it for most people. The concern really applies to anyone relying heavily on almond milk as a primary protein source, which its 1-gram-per-cup content makes impractical regardless of amino acid quality.
Who Should Think Twice About Relying on Almond Milk
If you’re using almond milk as a straight swap for cow’s milk or soy milk and counting on it for protein, you’re getting far less than you think. This matters most for growing children, older adults at risk of muscle loss, and anyone on a plant-based diet with limited protein variety. In those situations, soy milk is a closer nutritional match to dairy. Almond milk works fine as a low-calorie liquid for cereal, coffee, or cooking, but treating it as a protein source requires pairing it with lysine-rich foods throughout the day.