Can you eat two protein-rich food items together?

The advent of internet has made it possible for people to come across various strange food concepts, outlandish fad diets and absurd ideas about what to eat and how to eat it. Ease of creating and sharing videos on social media platforms has worsened the situation and largely contributed to a nutrition misinformation pandemic. This has led to confusion and scepticism among those who seek genuine and scientifically backed information regarding nutrition and balanced diets. One question that especially intrigues many people in India is “Can we eat two protein-rich food items together in a meal or for lunch?”

So, can you eat two protein-rich items together?

According to certain branches of alternative medicine, if the human body is unable to digest food properly, a whole host of health problems (diabetes, heart disease, and other chronic disorders) can start surfacing. According to them, one of the most important determinants of healthy digestion is the combination of foods that we eat. Practitioners of alternative medicine claim that two foods that may be highly nutritious and beneficial when eaten alone, may react with each other negatively when eaten together. And hence, the digestive system might be negatively affected. So, it is often believed that a combination of eggs and cheese, beans and curd, milk and eggs, curd and fish, and so on, are harmful to the body.

So, is there some truth to this? 

Food composition of common meals in India and abroad

Ancient Indian food traditions have always combined two or more protein-based foods in a meal and even in recipes. Hello Bengali doi maach and Gujarati khichdi kadi! Every regional cuisine or a thali has multiple protein-based foods in a single meal. If you consider the South Indian traditional banana leaf meal, you will always see sambar (a dal-based preparation) served along with curd rice or a milk-based payasam. A popular combination in Tamil lunches is parupuusuli (vegetable with steamed lentils) with morkozhambu (curd-based vegetable gravy). A North Indian Punjabi thali will always have a hearty, thick dal or rajma or paneer or even a tandoori chicken served with a tall glass of lassi. In all these cases, two or more protein items are combined for one meal.

Also, chicken and fish recipes across the globe use curd as a marinade, since it is a wonderful tenderiser and adds moisture to the meat. Thus, combining proteins isn’t an alien concept in Western cuisine either, and there are a number of recipes that combine high-protein chicken with cheese (in French cuisine) or beans with cheese (in Mexican cuisine). Meat-filled lasagne with ricotta and parmesan cheese is a popular dish from Italy that combines different proteins as well. 

Nutrition science and protein

Anecdotes apart, let’s see what modern research and science has to say about combining proteins. But first, let’s see why your body needs protein and how the body treats protein it receives from the food you eat.

1. Protein is one of the most important substances in your body, and about 17% of your body is made up of protein.
2. Protein is required for the formation of muscles, hair, nails, eyes, organs, genetic material, hormones, antibodies and enzymes. It is also required for the repair and maintenance of body tissues.
3. Protein digestion starts in your mouth when you chew your food. Some amount of protein digestion starts with the help of the enzymes amylase and lipase, which are present in your saliva. These enzymes mostly break down carbohydrates and fats.
4. Once the partially-digested food reaches the stomach, the hydrochloric acid present in the stomach and an enzyme called protease, break it down into small chains of amino acids.
5. These amino acid chains enter the small intestine, and more enzymes released by the pancreas and those present in the small intestine start breaking the chains, to release the individual amino acids.
6. These amino acids are absorbed into the bloodstream through the wall of the small intestine, along with other nutrients that are present in the food.
7. These individual amino acids then move through the bloodstream, and finally reach the different organs, where they carry out synthesis, repair and maintenance.

Understanding protein types and sources

Now, the protein in different kinds of food we eat is different, and how your body can absorb and utilise the amino acids depends on the type of protein. There are 20 different types of amino acids, but your body cannot make 8 of them. Therefore, these eight are called essential amino acids, and you have to get these from your diet. Meat, fish, eggs, soybean and milk and dairy products are considered high-quality protein foods as they contain all the essential amino acids. These are also called whole proteins or complete proteins. 

Other protein foods, such as nuts, dals, and seeds, contain only some essential amino acids. However, if you combine some of these protein sources, such as rice and beans, you can create a complete protein that contains all the essential amino acids. Some combinations of such foods are khichdi, rice with dal or rajma or chickpeas curry, hummus (chickpeas with sesame seed), and curd rice. It was previously thought that proteins from vegetarian sources must be consumed in the same meal so that the body can form complete proteins. However, now it is known that this is not necessary. The body can pool proteins from various foods consumed throughout the day, to form complete proteins, when needed. However, you might still find some nutritionists insisting that you combine different proteins in a single meal. This is primarily done to ensure that you consume enough protein in a day. 

In a nutshell

All in all, it makes sense to balance the intake of protein throughout the day. Eggs, milk, cheese or beans for breakfast can be followed by a fish or chicken meal for lunch, and soybean, yoghurt and legumes for dinner. You might want to incorporate small portions of lean meat or fish or paneer in your dinner too. The idea is to consume moderate amounts of protein throughout the day. And two protein-rich food items can definitely be consumed together, especially if you think that you might not be able to load up on protein for most other meals. Also, ensure that you don’t just focus on protein, but also consume enough veggies, fresh fruits and carbohydrates, so that you get all the essential nutrients.