Everybody knows we need fruits to stay healthy, because of all vitamins, minerals and other essential nutrients they contain. We know that nutrients, such as vitamin C, vitamin A, potassium, sodium, calcium are crucial to maintain a healthy body, but why exactly do we need vitamins and why do we need minerals? The 6 classes of essential nutrients, which will be explained below, are vital for proper growth, development and functioning of our body and a deficiency of an essential nutrient can cause different kinds of serious health problems.
Fruits are one of the most important foods, in particular because of the amount of vitamins they contain. If you want to make sure you eat nutritious fruits to stay perfectly healthy and you are not missing any nutrient, check out the top 10 vitamins and most important nutrients.
The 6 classes of essential nutrients the human body needs for a proper functioning, development and growth are carbohydrates, proteins and fats (macronutrients), which are needed in bigger amounts than the essential vitamins and minerals (micronutrients). Most fruits consist mainly of water - a vital nutrient - vitamins, minerals and carbs, while some fruits also contain protein and fats. Fruits and vegetables are therefore our main source of most vitamins and minerals and an extremely important part of our nutrition. These nutrients are called essential because the human body cannot synthesize them on its own to the amount needed. Some vitamins can be synthesized in small amounts by the human body and they can be obtained through animal products, since farm animals eat plants, but the daily amount required can only be obtained through the intake of fruits and vegetables.
*(daily recommended intake for an adult per day)
Vitamins are a set of organic compounds, grouped under alphabetical letters (A, B, C, D, E & K) and classified by their biological and chemical activity, not their structure. For instance, all B vitamins help the body to convert either carbohydrates, fats or proteins into energy and they are all water-soluble. Water-soluble vitamins cannot be stored by the body, so they have to be obtained by nutrition on daily basis. Fat-soluble vitamins (A, D, E & K), on the other hand, can be stored in the body for longer periods. Eating fat is therefore necessary in order to absorb the vitamins, thus a lack of fat intake leads to deficiency of these fat-soluble vitamins. The biochemical functions of vitamin groups are very diverse and even within a group each vitamin has its special functions.
Vitamin A (3mg)
Vitamin A comes in different forms, though in foods it can be found in two principal forms: retinol and carotenes (alpha-carotene, beta-carotene, gamma-carotene). Vitamin A has multiple functions; it promotes a healthy vision, hair, skin and a healthy immune system. It acts as an antioxidant and is important for growth and development, especially for bone growth, reproduction, cell recognition and embryonic development. Fruits that contain lots of vitamin A are papayas, cantaloupes, grapefruits, guavas, mangos, passion fruits, tomatoes and watermelons.
Vitamin B1 / Thiamine (1.5mg)
Vitamin B1 is necessary for carbohydrate metabolism, thus producing energy. It is necessary for a proper nerve functioning and for DNA and RNA production, therefore a deficiency is crucial for the nervous system, for brain as well as for heart health. Fruits with higher amounts of vitamin B1 are avocados, cherimoyas, guavas, grapefruits, dates, grapes, mangos, pineapples and watermelons.
Vitamin B2 / Riboflavin (1.7mg)
Vitamin B2 is important for energy production, since it helps to break down proteins, fats and carbs. It works as an antioxidant protecting our body from free radicals that can damage DNA and cells. These free radicals can cause disruptions of living cells by “stealing” electrons from them. When too many cells are “attacked” by free radicals and too many of these particles exist, diseases can develop, like heart diseases or cancer. Thus it is important to consume nutrients that act as antioxidants. Vitamin B2 is also important for a healthy skin, growth, red blood cell production and for the processing of vitamin B6 and B9. Fairly good fruit sources for vitamin B2 are apricots, bananas, cherimoyas, dates, lychees, mangos, passion fruits, pomegranates and prickly pears.
Vitamin B3 / Niacin (20mg)
Vitamin B3 acts as an antioxidant and plays an important role in the nervous system and in energy production. It is needed for DNA repairing, a healthy digestive system and healthy skin. Vitamin B3 is mainly found in animal products, but fruits like avocados, peaches, lychees, apricots, dates, guavas, mangos, nectarines and passion fruits contain a fair amount of it.
Vitamin B5/ Pantothenic acid (5mg)
This vitamin is, as are all B-vitamins, primarily important for energy metabolism. It participates in many crucial biological roles, like signal transduction and enzyme activation and deactivation. A deficiency can cause a wide range of negative health effects, such as apathy, irritability, fatigue or neurological symptoms, like numbness or muscle cramps. Fruits that contain higher amounts of vitamin B5 are avocados, dates, guavas, pomegranates, raspberries, strawberries and grapefruits.
Vitamin B6 / Pyridoxine (2mg)
Vitamin B6 is crucial for the synthesis of neurotransmitters, promoting a healthy nervous system. It assists in cell health, energy production and utilization, as well as hormonal optimization. It helps to promote a healthy immune system and is necessary for the absorption of the essential vitamin B12. Fruits that contain higher amounts of vitamin B6 are acerolas, prunes, avocados, papayas, oranges, cantaloupes and bananas.
Vitamin B9 / Folate (400µg)
Vitamin B9 is involved in the metabolism of important amino and nucleic acids, essential for cell division and therefore crucial during pregnancy and for fertility. It is also very important for red blood cell production, muscle building, iron formation, cell enhancement and skin cell building and repairing. It especially helps promoting heart and mental health.
Fruits that contain much vitamin B9 are avocados, oranges and tropical fruits, such as mangos, papayas, guavas, kiwifruits, bananas and pomegranates.
Vitamin C (60mg)
Vitamin C is a very important vitamin, as it plays key roles in many important body functions. It is necessary for the synthesis of collagen, providing structure to skin, blood vessels, bone and ligaments. It therefore helps for wound healing and for forming scar tissue, as well as it repairs and maintains teeth, bones and cartilages. It acts as an important antioxidant, keeping the immune system safe, especially since it aids absorbing essential iron. Vitamin C is most commonly linked to fruits, since many fruits contain high amounts of vitamin C, like guavas, papayas, black currants, kiwifruits, lychees, jujubes, strawberries and it is abundant in citrus fruits, such as nectarines, pomelos, oranges, limes and lemons.
Vitamin E (12mg)
Vitamin E comes in 8 different forms, the most common being the alpha form. It has many different functions in the body, but mostly it acts as an antioxidant, protects cells and helps promoting a healthy vision. It also helps to promote a healthy immune system and is involved in repairing body tissues. Fruits that contain the highest amount of vitamin E are mamey sapotes, all kinds of avocados, kiwifruits and black currants.
Vitamin K (120μg)
Vitamin K is crucial for the creation of blood clots and for a proper bone metabolism. It is also very important for the regulation of blood calcium levels. Fruits that contain lots of vitamin K are kiwifruits, avocados, blueberries, blackberries, pomegranates and rhubarbs.
Minerals are naturally occurring chemical elements that can’t be be produced by our bodies and must be provided by our diet. They are vital for biochemical processes, as they serve structural and functional roles and act as electrolytes. The five major minerals in the human body are calcium, phosphorus, potassium, sodium and magnesium. Minerals found in low concentrations are called trace elements. Trace elements with a very important biochemical function are iron, cobalt, copper, zinc, manganese, molybdenum, iodine, and selenium.
Potassium helps maintaining electrolyte balance in the body, as well as the fluid volume balance inside and outside of cells. It prevents the excess rise of blood pressure with increased sodium intake and is essential for nerve, heart and muscle function. Therefore, a deficiency in potassium can create high blood pressure (hypertension), fatigue and irritability.
Fruits with a high amount of potassium are avocados, guavas, bananas, passion fruits, kiwi fruits, apricots and pomegranates.
Calcium is mostly found in dairy products and less in fruits, but knowing which fruits contain a fair amount of calcium is especially important for vegans. It is a crucial mineral, particularly important to maintain and build strong bones and teeth. It helps blood vessels move blood through the body, helps to release important hormones and enzymes and is essential for nerve cells, thus important for brain and muscle function. These fruits can help you to pimp your calcium level: hibiscus, kumquats, rhubarbs, tamarinds, all kinds of currants, oranges and prickly pears.
As the second most abundant mineral in the body, phosphorus is crucial for us, helping cellular reproduction, particularly cell membranes and nucleic acids and
contributing to the growth and repair of tissues. It also filters waste and plays an important role in energy production and bone health maintenance. Fruits like tamarinds, rowals, avocados, currants, groundcherries, and passion fruits contain the highest amounts of phosphorus.
Magnesium is very important for bone development and especially for the proper functioning of various metabolic processes, since it is a co-factor in more than 300 enzyme systems. These systems regulate reactions important for muscle and nerve functions, energy production, protein synthesis, blood pressure regulation and blood glucose control. Fruits that contain a fair amount of magnesium are hibiscus, tamarinds, prickly pears, bananas, apples, avocados and plantains.
Zinc is not needed in high amounts, but it is still a very important mineral, stimulating the activity of minimum 100 enzymes. It is necessary for growth, DNA synthesis, for a healthy immune system and wound healing. It also helps to reduce diarrhea and affects learning and memory. Zinc is more commonly found in meat, seafood and vegetables, while following fruits contain the highest amount of zinc; avocados, rowals, blackberries, raspberries and pomegranates.
Iron is an essential mineral for red blood cells and for the transportation of oxygen in our body. Therefore deficiency in iron causes fatigue and a weaker immune system. It pairs the best with vitamin C and is very important for skin, hair, nail and cells health. Fruits that contain the highest amount of iron are rowals, tamarinds, hibiscus, native persimmons, elderberries, mulberries, abiyuchs and black currants.
The human body contains mostly water, in fact, 50-80% of our body weight is water. It is a crucial nutrient, playing a key role in all biochemical reactions that happen in the body, from transporting nutrients to cells to regulating body temperature. It assists in removing waste products from the body, protects joints, the spinal cord and tissues. Fruits and vegetables contain lots of water and are therefore helpful to stay hydrated.
Fruits with a very high water content are watermelons, oranges, strawberries, rhubarbs and Florida grapefruits.
Carbs (saccharides) consist of simple sugars (glucose, fructose or galactose) forming different kinds of chains. When these sugar molecule chains break down into simple sugars (monosaccharides), energy is released. Since glucose is the fuel for all body functions, carbs are our main source of energy. Depending on the amount of simple sugars in the chain, it is called a disaccharide, oligosaccharide or polysaccharide - containing two, eight or more then eight simple sugars. Monosaccharides and disaccharides are called simples carbs, since they break down quickly and provide you with energy for a short period of time. Oligosaccharides and polysaccharides are complex carbs, taking longer to break down, thus providing you with energy for a longer period of time. The regular release of blood sugar prevents blood sugar lows and binges, while candy or sugary drinks consist of simple sugars and create sudden blood sugar lows. Fruits with carbs contain mostly complex ones, like fiber and starches. Dietary fiber in particular is very healthy, since it enhances digestion and is important for absorbing other nutrients. Water-insoluble fiber is linked to a reduced diabetes risk, while water-soluble fiber controls blood sugar levels and can help lower blood cholesterol. Many studies suggest that fructose is bad for human metabolism, although there is insufficient proof to show that it has a negative effect. Contrary, fructose is preferable over glucose in sweetened foods. Of course eating an excessive amount of fruits containing lots of glucose and fructose can cause negative symptoms, like it happens with every excessive intake. The fruit with the highest amount of carbohydrates is by far the tamarind. If you prefer a lighter, but still nutritious snack these fruits are a good pick: bananas, all kinds of apples, breadfruits, jackfruits, rowals, mamey sapotes and passion fruits.
Proteins and fats are nutrients less common in fruits, but abundant in animal products or nuts, beans and lenses. Fruits with a higher amount of proteins are, for example, avocados, passion fruits, guavas, sugar apples and rowals. Avocados and apples also contain the highest amount of healthy unsaturated fatty acids, together with casaba and cantaloupe melons. Proteins and fats are essential nutrients, due to the complex and vital body functions they are needed for. We need to eat fats, but it is important to eat much more healthy unsaturated fatty acids than unhealthy saturated fatty acids. Fruits can be therefore a healthy way of eating these unsaturated fats. If you are interested in knowing more about these two essential nutrients, check out our ultimate nutrition guide.