How to Get Enough Protein While Following a Vegetarian Diet


*DISCLAIMER: this is not a substitution for professional medical advice provided from your doctor or medical professional including a Registered Dietitian. This blog’s purpose is to elaborate on the idea of being vegetarian and getting enough protein and should not substitute or supplement medical advice provided in a clinical or outpatient setting by a medical professional. If you would like to know more about becoming a vegetarian or ensuring that you are receiving adequate nutrition on your specific diet plan, please consult a medical professional.

Written By: Heather Gerrish, RDN

Following a vegetarian diet and lifestyle can be a big change for an individual accustomed to another type or variation of diet. Some of the biggest changes might not be what you think - and should be addressed early on in the transition to pursuing a vegetarian diet. This blog will review some of the concepts, nutritional parameters and markers that should be included in developing a vegetarian diet profile and that should be considered in the long term adherence of this specific dietary practice.

The first consideration includes the purpose, or why the individual (or you!) is changing their dietary practices to include a vegetarian diet (if you have not followed a vegetarian diet in the past). One concern, as with any restrictive/elimination diet parameter, is the tendency for those a history of eating disorder and related behaviors to follow diets that are restrictive in nature. [Just a side note and something to consider]. Other considerations as to why one might change their diet to vegetarianism is personal, economic, value driven or spiritual beliefs. No one is wrong for following their own path and pursuing a vegetarian lifestyle should be accepted with open arms! Everyone is different, and every lifestyle is therefore also unique and styled appropriately to what each individual believes and embraces.  

Aside from establishing a safe practice and acknowledging the reason behind any “diet” change is the nutritional parameters that should be assessed and kept a close eye on for those just starting out on a vegetarian diet.

When not consuming animal products, often there is an initial struggle to consume enough protein because prior to this change, the primary source of protein might have been meat (chicken, beef, fish etc) or other animal derived protein sources. Switching to a vegetarian diet can be tricky at first, but with the right tools and plan in place it can definitely be done, and done well!

The key nutrients to look for (and even supplement in some cases, but this another topic to bring up with your medical doctor if you are at all concerned) include:

  • Vitamin B12

  • Iron

  • Omega 3’s [α-linolenicacid, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)]

These specific nutrients are commonly in animal products (vitamin B12 and iron found in meat such as chicken or beef and omega 3’s found in fish including salmon). When following a vegetarian diet, one does not consume these items and therefore needs to seek out alternatives to ensure adequate intake. This could be in the form of supplementation or navigating alternatives such as nuts and seeds (walnuts being a great source of Omega 3’s), dark leafy vegetables and staying in close communication with your primary care provider regarding any potential nutrient deficiencies.

A vegetarian diet has its perks, with a emphasis on legumes, fruits and vegetables, whole grains and nuts and seeds (yum!) but a “vegetarian” diet can also consist of food products that are technically “vegetarian” but contain minimal nutritional benefit and are highly processed. Think artificially flavored cheese puffs and soda - technically vegetarian, but NOT exactly what we are hoping for.

Now that we have reviewed some of the basic parameters of a vegetarian diet, let’s get back to protein.

When following a vegetarian diet one should watch for complementary proteins, but before we dive into this topic first we need to review the concept of amino acids. There are 20 amino acids, 9 of which are essential (meaning our body requires outside sources and cannot synthesize these itself). Amino acids are also found in animal proteins (think muscle!) and of course, when a vegetarian is not consuming these amino acids commonly found in animal proteins, there can be some trouble down the road.

To help with this, the idea of “complementary proteins” has become a common topic for vegetarians to cover in terms of nutrition education in order to best plan for and receive adequate nutrition while following a this diet. The overall concept of “complementary proteins” plan is to consume a variety of foods that contain varied amino acid profiles to best “complement” what your body needs (as in amino acid pairs). This is a great overview of what this concept might look like by definition from the Food and  Drug Administration (FDA)(1):

  • Complete proteins contain all of the essential amino acids in adequate amounts. Animal foods (such as dairy products, eggs, meats, poultry, and seafood,) and soy are complete protein sources.

  • Incomplete proteins are missing, or do not have enough of, one or more of the essential amino acids, making the protein imbalanced. Most plant foods (such as beans and peas, grains, nuts and seeds, and vegetables) are incomplete protein sources.

  • Complementary proteins are two or more incomplete protein sources that, when eaten in combination (at the same meal or during the same day), compensate for each other’s lack of amino acids. For example, grains are low in the amino acid lysine, while beans and nuts (legumes) are low in the amino acid methionine. When grains and legumes are eaten together (such as rice and beans or peanut butter on whole wheat bread), they form a complete protein.

This is another great link from Bastyr University on complementary proteins (2) if you want to read more:

Bastyr also has a great list of common examples as to what this might look like for a vegetarian looking to create a well-rounded (and complementary protein based!) meal:

Here is a list of some food pairings that make a complete protein (2) and which are excellent vegetarian sources of protein outside of being complementary protein pairs:

  • Legumes with grains, nuts, seeds or dairy

  • Grains with dairy

  • Dairy with nuts

  • Dairy with nuts/seeds and legumes

Protein intake does not have to be too complicated, and with focusing on these sources you likely will find yourself meeting your protein goal. The key is to approach this diet with the mindset of fueling your body with these types of foods and not simply consuming “vegetarian” items because they are “vegetarian” (remember those cheese puffs?) and listening to what your body. Also, it is important to talk with your doctor and inform him or her of any changes to your normal routine so they can best help you monitor your status of the mentioned nutrients. Additionally, obtaining a referral for a consultation with a Registered Dietitian can further help you develop a sound vegetarian diet and learn more about how you can best implement this practice for your short and long term health.  

Overall, incorporating greater variety of fruits and vegetables and focusing on whole foods is an excellent method to incorporate into any nutrition practice. To keep in mind this emphasis and not lean towards more processed vegetarian “fast-food” like items is also an essential component of implementing this diet structure. If you currently are practicing a vegetarian diet, keeping in mind these factors will be an important component to long term adherence and ensuring that you are getting enough, or if you are thinking about adapting this structure, preparing beforehand and reaching out to your doctor and even visiting a Registered Dietitian would be a great way to become more educated and aware of the things to watch for and monitor while following this type of diet.




Danielle Gray