Maize vs Rice - Health impact and Nutrition Comparison

Summary

Both foods contain essential vitamins and minerals and can lead to adverse effects if overused.

Corn is predominantly richer in sugar and protein, vitamins A, C, K, E, B2, B5, also choline and fiber. On the other hand, rice is higher in carbs, calories, iron, calcium, and vitamin B9. So the correct choice depends on what the organism needs.

Introduction

Corn, also known as maize, is a cereal grain that originates in parts of South America, particularly domesticated by indigenous people of Mexico. Corn production surpasses rice production, but most of the crop is used in agriculture as animal feed or to produce corn ethanol, starch, and syrup, instead of directly being consumed by people as food. Corn is a warm-season annual crop but is grown all year round in greenhouses. It is an excellent source of vitamins and micronutrients.

Rice is the seed of a grass species, classified as a cereal grain as well. It is said to provide about twenty percent of all human caloric intake worldwide. Rice can be grown practically in every country, but its parent species are native to eastern Asian countries and certain parts of Africa. Overall, it is an easy and cheap source of calories and micronutrients all year round, including ecotypes with different textures, tastes, and nutritional values.

In this analysis, we discuss what qualities the two foods have in common, but more importantly, their main nutritional differences and impacts on health.

Nutrition

Corn is richer in sugars and protein, but rice is higher in calories and carbs due to its starch content. Corn has a lower glycemic index, while rice is the preferred choice in a low-fat diet.

Vitamins

Maize wins in this category.

Corn contains vitamin A, vitamin E, vitamin C, and vitamin K, whereas rice entirely lacks these vitamins. Corn is also richer in most B vitamins, such as vitamins B2 (riboflavin), B3 (niacin), and B5 (pantothenic acid) in particular, except for vitamin B9 (folate).

Rice contains more vitamin B9 compared to corn.

Vitamin Comparison

Vitamin comparison score is based on the number of vitamins by which one or the other food is richer. The "coverage" chart below show how much of the daily needs can be covered by 300 grams of the food

Maize

7

:

2

Rice

Contains more Vitamin A +∞%

Contains more Vitamin E +75%

Contains more Vitamin C +∞%

Contains more Vitamin B2 +323.1%

Contains more Vitamin B3 +19.9%

Contains more Vitamin B5 +83.8%

Contains more Vitamin K +∞%

Contains more Folate +38.1%

Equal in Vitamin B1 - 0.163

Equal in Vitamin B6 - 0.093

Maize

Rice

Contains more Vitamin A +∞%

Contains more Vitamin E +75%

Contains more Vitamin C +∞%

Contains more Vitamin B2 +323.1%

Contains more Vitamin B3 +19.9%

Contains more Vitamin B5 +83.8%

Contains more Vitamin K +∞%

Contains more Folate +38.1%

Equal in Vitamin B1 - 0.163

Equal in Vitamin B6 - 0.093

Minerals

When it comes to micronutrients, the winner depends on what you’re looking for. Corn contains more potassium, magnesium, and phosphorus, whereas rice is richer in iron, calcium, and copper.

Corn is also higher in sodium.

Both foods are equal in amounts of zinc contained.

Mineral Comparison

Mineral comparison score is based on the number of minerals by which one or the other food is richer. The "coverage" chart below show how much of the daily needs can be covered by 300 grams of the food

Maize

3

:

5

Rice

Contains more Magnesium +208.3%

Contains more Phosphorus +107%

Contains more Potassium +671.4%

Contains more Calcium +400%

Contains more Iron +130.8%

Contains less Sodium -93.3%

Contains more Copper +27.8%

Equal in Zinc - 0.49

Maize

Rice

Contains more Magnesium +208.3%

Contains more Phosphorus +107%

Contains more Potassium +671.4%

Contains more Calcium +400%

Contains more Iron +130.8%

Contains less Sodium -93.3%

Contains more Copper +27.8%

Equal in Zinc - 0.49

Fortification

When speaking of nutrients, it is important to pay attention to fortification (enrichment or adding micronutrients to food). In more recent years, the World Health Organisation (WHO) has developed guidelines for fortifying rice with iron, zinc, vitamin A and B-complex vitamins to reduce malnourishment (1).

Corn and Rice Starches

Starch or amylum, a polymeric carbohydrate, can be extracted from both plants, but the two have different physicochemical and morphological properties. Corn starch has a greater average granule size and amylose content. Rice starches are more challenging to extract and profitably use in products. It cooks at a higher temperature and does not form a gel as strong. That is why corn starch is much more common in households (2).

Health impact

Corn is higher in fiber, as well as choline, which is an essential nutrient for cellular growth, DNA synthesis, and metabolism that the body gets mostly from dietary sources.

There are two types of choline: fat-soluble and water-soluble. The choline in corn is fat-soluble, so the body absorbs it from the gastrointestinal tract. Choline is an essential nutrient for fetal brain development and greatly improves cognitive functioning in older people. It is a part of the vital neurotransmitter acetylcholine. Choline deficiency can lead to fatty liver disease and liver damage, muscle damage, and cognitive decline, among other issues (3, 4). So corn can provide nutrients that are necessary for every system of the body.

Fiber is essential for the health of the gastrointestinal tract, controlling blood sugar and cholesterol levels. Refined and processed white rice lacks this element, while brown rice contains much more. To see more information about the differences between these two types of rice, you can look at our White rice vs. Brown rice comparison.

Corn is also higher in most vitamins, predominantly vitamins A, K, C, B2, and B5, that play a significant role in human metabolism.

Vitamin A is a fat-soluble vitamin that plays a large role in growth and development, the immune system, and vision. It is partly responsible for the yellow pigment of corn. The retina uses vitamin A to synthesize rhodopsin that later breaks down when absorbing light, sending a neuronal signal to the brain about the picture in front of your eye. Therefore, vitamin A deficiency leads to reversible vision loss, especially in dim-lit spaces and immune system and skin issues.

Vitamin K is an essential part of the body’s coagulative response, creating blood clots and preventing excessive bleeding.

Vitamin C or ascorbic acid is only found in sweet corn and is widely known for its crucial role in the immune system. It is also involved in tissue reparation and the synthesis of certain neurotransmitters. Corn has the highest total antioxidant activity due to its vitamin C content among other grains such as rice and wheat.

Vitamin B2, also known as riboflavin, is required for cellular respiration. Its deficiency causes a variety of issues, such as migraines and stomatitis. It has also been studied to lower the risk of colorectal cancer (5). Corn, being the better source of these vitamins, can play a significant role in the healthy processes of the organism, as well as prevent deficiencies. Overall scientific evidence suggests that the right amount of corn consumption reduces the risk of developing chronic diseases: type 2 diabetes, obesity, cardiovascular and digestive issues (6).

As good as corn is for human health, it has been known to cause a malnutrition issue if overused, stemming from its lack of a few amino acids, namely lysine and tryptophan. Corn can also quickly lose its vitamin B3 content, also known as niacin, if cooked improperly, a process called nixtamalization. Niacin deficiency, especially combined with a tryptophan deficiency, causes a disease called pellagra. The main symptoms include diarrhea, inflamed skin, and cognitive issues. The lack of tryptophan leads to low serotonin levels, leading to depression. It is often referred to as the disease of four “D”s: diarrhea, dermatitis, dementia, and death (7, 8).

Some African countries where the people endure famine and use corn as their primary food source suffer from a disease called kwashiorkor due to severe protein malnutrition. It mainly affects infants and children and is rarely seen in developed countries (9).

On the other hand, rice contains less sugar and sodium and significant vitamins, such as B9, B1, B2, and B3.

Vitamin B9, also known as folic acid or folacin, plays an important role in forming DNA and RNA necessary for normal cell division and the formation of human germ cells. It also controls the level of amino acid homocysteine in the blood. High levels of homocysteine in the blood are associated with heart disease. Vitamin B9 deficiency also leads to megaloblastic anemia. Pregnant women with low levels of folate are at risk of having children with neural tube defects.

As previously discussed, vitamin B3 deficiency causes pellagra, a large issue if one misuses corn, while rice does not create the same problem. Even though rice contains satisfactory levels of essential amino acid tryptophan, it lacks lysine unless it has undergone biofortification.

Vitamin B1 or thiamine deficiency symptoms such as muscle weakness and neuritis can be partially treated with some varieties of rice with a high thiamine content.

A negative aspect of overusing rice or producing it in wrong conditions is the arsenic concern. It is a natural resource in the soil and can be found in rice, but it can turn into a larger issue when used to make infant food. High levels of arsenic are considered oncogenic and play a role in coronary heart disease (10).

Rice plants can sometimes be infected with microorganisms such as the bacterium called Bacillus cereus, the spores of which can later be contained in cooked rice, producing an emetic (vomit-inducing) toxin.

Sources

1. https://www.who.int/elena/titles/rice_fortification/en/
2. https://core.ac.uk/reader/82100590
3. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6008955/
4. Plasma free choline, betaine and cognitive performance: the Hordaland Health Study
5. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5514841/
6. https://www.sciencedirect.com/science/article/pii/S2213453018301009
7. https://pubmed.ncbi.nlm.nih.gov/14693013/
8. https://www.sciencedirect.com/science/article/abs/pii/0024320575901113
9. https://www.ncbi.nlm.nih.gov/books/NBK507876/
10. https://www.researchgate.net/publication/287284991