Nutrient Deficiencies and Plant-Based Diets

Plant-based diets come across as being high maintenance.

Claims of needing to “carefully plan” and be “nutritionally conscious” scare many people into not changing their diet.

However, the need to carefully plan a plant-based diet is a myth.

It’s not just those who switch to a plant-based diet should be nutritionally conscious, but everybody should be nutritionally conscious. Whether a person follows a plant-based diet or not, individuals should be aware of what nutrients they are (or aren’t) putting into their bodies.

Everybody needs to be aware of the fat, proteins, carbohydrates, sugars, calories, fibers, vitamins, minerals, phytonutrients and antioxidants that they eat. Just as a person on a healthy diet should aware of the abundance of health-promoting nutrients they put into their bodies, a person who eats unhealthily should be knowledgeable about the lack of nutrients that provide benefits in their diet.

Following are the facts about mythological deficiencies that individuals need to be aware of when “planning” their plant-based diet.


You don't need meat for protein

The protein myth is a joke among the plant-based and vegan community.

Vegans are always asked, “where do you get your protein?”.

Vegans get protein from all their foods because all foods contain protein. Protein is necessary to keep all foods together. Even fruits, which are mostly made up of carbohydrates, contain protein. Fruits such as dates contain very little protein; about 3% of their calories come from protein.

Lentils contain plenty of healthy protein

Lentils supply more than enough protein

In the middle of the plant-based spectrum, we have foods that contain a moderate amount of protein. Tomatoes provide 12% of their calories through protein.

Finally, we have foods that are high in protein: lentils. Mature lentils are 27% protein. The human body only needs 10% of calories from protein. I suggest having protein be between 10-20% of an your caloric intake.

A higher protein diet can have negative longevity implications and negative health implications. In addition, the greater percentage of protein that is consumed, the lesser amount of carbohydrates that is ingested. The body prefers to run off of carbohydrates.

I have already talked about they myth of complete proteins in Macronutrients:

The myth of “complete protein” is a lie.

A “complete protein” is a food that contains all 8 amino acids in certain amounts.  Meat is a “complete protein” because that is essentially what muscle is—a combination of these the amino acids in large proportions.

Plant sources of protein are often called “incomplete proteins” by some sources because they do not contain all amino acids in the same amount. Many people say that plant sources need to be combined in certain ways in order to create “complete proteins”, like beans and rice. These foods are supposed to be eaten together because where one is lacking the other makes up for the difference.

This isn’t necessary. . .

Understand that amino acids don’t need to be eaten in the same amounts because different essential amino acids are used in varying amounts. Therefore, we don’t need to worry about getting even amounts of each amino acid, only sufficient amounts of each throughout the day.

 Fun fact: Unknown to most people, 100 calories of broccoli has more protein than 100 calories of steak. 


Plants get labeled with having lesser quality iron than animal sources.

A reason for this is that plants contribute non-heme iron while animal sources give heme iron. While this is technically incorrect because both plant and animal sources contain both, heme iron in plant sources is negligible. Animal sources provide roughly equal proportions of the two types of iron.

Put simply, heme iron is iron that is attached to a protein called heme protein. Non-heme iron is not attached to this protein.

It’s generally said that heme iron is better absorbed than non-heme iron, but both types have a large range for their absorption rates. Heme iron is absorbed at a rate between 7-35%; non-heme iron is absorbed at a rate between 2 and 20%.

Yes, the average rate of absorption of heme iron is higher, but absorption will also depend on an individuals health and other dietary choices. If an individual is lacking in iron then more iron will be absorbed by the body; the opposite is also true.

Calcium inhibits iron absorption and vitamin C encourages it.

Red meat is touted as the best source of iron.

Evidence begs to differ.

Look at the amounts of iron in two selected foods:  90% lean cooked ground beef and raw spinach.


Beef is known to have a lot of iron. But how much does it really have?

In 182 calories of the beef, there is a total of 2.5 mg of iron.

From my explanation above, roughly half of that iron is heme and half of that iron is non-heme. Assuming the average absorption rate of both the heme and non-heme iron, a total of 16% of the total iron will be absorbed. That means that 0.4 mg of iron will be absorbed.


Spinach provides a large amount of iron

182 calories of spinach is a LOT of spinach.

182 calories worth of spinach contains a whopping 21.4 mg of iron.

Since the amount of heme iron in the spinach is negligible, nearly all of the iron absorbed is non-heme. 11% of 21.4 mg of iron results in 2.4 mg of iron being absorbed.

The spinach beat the beef by a long shot.

CalciumMilk isnt as healthy as you think


Dairy milk is the first product that comes to mind when calcium is in question.

However, dairy products such as milk, yogurt and ice cream have been unjustly placed on a pedestal. Other amazing sources of calcium have been forgotten, like kale and oranges.Citrus fruits are good sources of calcium

The standard American diet is high in both fat and protein and is low in carbohydrates. The amount of protein that individuals consume affects how much calcium our bodies need.

The body needs more calcium on a high protein diet in order to function. Lower protein intake results in a decreased need for calcium.

Considering this, the DRI in the US for calcium is simply too high to apply for people on a high carbohydrate, plant-based diet. Americans are encouraged to get at least 1000 mg of calcium per day. A person eating a balanced, plant-based diet would be healthy with half that amount of calcium.

Compare calcium and milk:

  • 60 calories of whole milk contains 113 mg of calcium.
  • 60 calories of kale has 162 mg of calcium.

Again, the animal product has been trumped by the plant food.

A healthy, nutritious diet

A vegan, i.e. plant-based, diet is not lacking in nutrition. It is healthy and provides nearly all the nutrition you need.

A plant-based diet is lacking no more than any other unenriched or unfortified diet is.

In fact, if all food enrichments and fortifications were removed from processed food, there is a high likelihood that the standard American diet would be revealed for what it truly is: empty and lacking.

Breakfast cereals, milks, bread and even salt are all fortified with a range of nutrients. These added nutrients combat chronic diseases and nutrient deficiencies that would otherwise run rampant in the USA.

A plant-based diet is not difficult to eat with proper knowledge of healthy food choices and a sufficient number of calories. Take a supplement for vitamin B12 and get sunshine for the vitamin D and there should be very few deficiencies or problems on plant-based lifestyle.


  • Updated a couple of years ago
Sara Binde

Sara is a health and nutrition coach. She advocates for a whole foods plant-based lifestyle and teaches the world how to achieve weight loss.