Nutrients
Background information on the nutrients contained in the Swiss Food Composition Database is presented below. All references to recommendations and requirements for the daily intake refer to healthy adults aged between 18 and 65 and are derived from the nutrient reference values for Switzerland published by the Federal Food Safety and Veterinary Office FSVO.
Energy
The energy requirement of a person depends on many factors such as gender, height, weight, body composition and naturally on physical activity. A balanced, sufficient energy supply is demonstrated by a stable body weight.
According to the nutrient reference values for Switzerland, the daily energy requirement of a women average in age, height and weight lies between 1861 kcal and 2147 kcal, for a moderately active lifestyle. A man of average age, height and weight requires between 2305 kcal and 2672 kcal, for a moderately active lifestyle.
The energy content of a food which can be utilised by humans cannot be determined precisely, but is calculated by means of factors. The factors take into account that the human organism can only make use of part of the energy present in a food.
In the Swiss Food Composition Database the energy content is given both in calories (kcal) as well as in kilojoules (kJ). The values are calculated using the conversion factors from the Swiss Ordinance on Information on Foodstuffs FoodO (Annex 12 Art. 26 para. 1) (SR 817.022.16, status 19.11.2019):
| Carbohydrates | 4 kcal | or | 17 kJ | per gram |
| Protein | 4 kcal | or | 17 kJ | per gram |
| Fat | 9 kcal | or | 37 kJ | per gram |
| Alcohol | 7 kcal | or | 29 kJ | per gram |
| Dietary fibres | 2 kcal | or | 8 kJ | per gram |
| Organic acids* | 3 kcal | or | 13 kJ | per gram |
| Polyols* | 2.4 kcal | or | 10 kJ | per gram |
* These values are rarely available. They are not published but are taken into account when calculating the energy content.
Carbohydrates
The carbohydrates are a large group of nutrients that are mainly found in plant foodstuffs, but also in dairy products. Quantitatively, plant starch is the most important carbohydrate. Other carbohydrates are glucose (dextrose, fructose), lactose, maltose and saccharose.
According to the nutrient reference values for Switzerland, 45-60% of the daily energy requirement should come from carbohydrates.
Information on the available carbohydrates and on starch and sugar* can be found in the Swiss Food Composition Database. Starch and sugar make up the major part of the available carbohydrates. The available carbohydrates are generally calculated using the following formula: Carbohydrates, available (g/100g) = 100 – protein (g/100g) – fat, total (g/100g) – water (g/100g) – ash (g/100g) – dietary fibre (g/100g)
* The term “sugar” includes all mono and disaccharides, e.g. glucose, fructose, lactose, saccharose.
Dietary fibres
Dietary fibres (also known as roughage) are indigestible plant nutrients that inter alia have a positive effect on digestion. A distinction is drawn between soluble and insoluble dietary fibres. Soluble dietary fibres include beta-glucan (e.g. in yeast) and pectin (e.g. in apples). Nuts and wholemeal grains provide principally insoluble dietary fibres (e.g. cellulose). Refined products such as white flour contain almost no dietary fibre.
According to the nutrient reference values for Switzerland, adults should eat at least 30 g of dietary fibre per day. An adequate intake of liquid optimises the positive effect on digestion. In contrast, not enough liquid intake coupled with a high dietary fibre intake can lead to constipation.
Fat
Fats are found in both plant and animal foodstuffs and are a nutritional source of energy and essential fatty acids*. Moreover, fat-containing foodstuffs are an important source of fat-soluble vitamins (A, D, E, K).
According to the nutrient reference values for Switzerland , the daily fat intake should represent 20-35 % of the energy intake. From experience, at least half of the fat intake comes from “hidden” fats (such as dairy products, eggs, meat and nuts).
The data on fat in the Swiss Food Composition Database correspond to the total fat content (incl. triglycerides, cholesterol, phospholipids, etc.). The sum of the three fatty acid groups (saturated, mono-unsaturated and poly-unsaturated) is consequently less than the total fat content.
* Fatty acids are the most important components of fats. They can be subdivided into three groups: saturated, mono-unsaturated and poly-unsaturated fatty acids. The various fatty acids and fatty acid groups exhibit different effects and functions in metabolism.
Cholesterol
Cholesterol is a fat-related substance which is found mainly in animal foodstuffs (e.g. offal, egg yolk, butter) and can also be produced by the human organism. Cholesterol fulfils a number of important tasks, e.g. the synthesis of vitamin D and of various hormones.
Cholesterol from the diet plays only a minor role in influencing the blood cholesterol level. Cholesterol in the blood originates mainly from the body’s own production and not from the diet. From today’s scientific viewpoint, limiting the intake of cholesterol is therefore no longer justified.
Protein
Protein, also known as albumin, supplies the body with amino acids* that are required for the synthesis of the body’s own proteins (e.g. muscle protein, hormones, etc.). Proteins from animal foodstuffs such as meat, fish, eggs, milk and dairy products tend to be of higher value than plant proteins (e.g. from cereals, potatoes, nuts), as they contain a more optimal spectrum of amino acids. However, plant proteins can be greatly enhanced by combining them or in combination with animal proteins.
According to the nutrient reference values for Switzerland the daily requirement of proteins for a healthy adult is 0.83 g per kg weight.
Pursuant to the FDHA Ordinance on Information on Foodstuffs FoodO (Annex 1 Art. 2 and 6 para. 1) (817.022.16, status 19.11.2019), the protein content is calculated in the Swiss Food Composition Database by using the formula “nitrogen content x 6.25”. The use of a uniform factor of 6.25, however, means that for some foodstuffs the actual protein content is either overestimated or underestimated. Data on the specific conversion factors of nitrogen to protein can be found i.a. in publications of the FAO/WHO, e.g. FAO/INFOODS, Guidelines for Converting Units, Denominators and Expressions, Version 1.0, 2012.
* Amino acids are the building blocks of proteins. They are strung together into long chains. The sequence and type of amino acids determines the function of the protein.
Alcohol
Alcohol is an energy-supplying nutrient that is present in exceedingly small amounts in natural foodstuffs. The major sources of alcohol are alcoholic drinks and products prepared from them.
There are no recommendations for alcohol intake. Acceptable daily quantities are considered to be 10 g for women and 20 g for men. Children, adolescents, pregnant women and breast-feeding women should abstain from alcohol.
The alcohol content is listed in the Swiss Food Composition Database in grams per 100 ml or 100 g. These values are lower than the volume per cent figures for alcoholic drinks. A schnapps with 40 vol % contains about 32 g of alcohol per 100 ml.
Water
Water is present not only in drinks and soups but also in most foodstuffs. Fruit and vegetables in particular have a high liquid content (up to 95%).
Water makes up more than half of the human body and the daily losses of water (mainly from the kidneys, skin, lungs) have to be regularly replenished. An inadequate supply of liquid can lead to reduced physical and mental capacity as well as to constipation.
Daily requirements for water are around 2.5 litres. However, according to the Swiss food pyramid, 1 to 2 litres per day of fluid intake suffice. The remainder comes from food.
Vitamin A
Vitamin A (retinol) is a fat-soluble vitamin which is present only in animal foodstuffs. Plant foodstuffs contain vitamin A precursors (provitamins A) such as beta carotene that the body can partially convert into vitamin A.
According to the nutrient reference values for Switzerland , women require 650 μg and men 750 μg of vitamin A (in retinol equivalent) per day. The tolerable upper intake level of Retinol is 3 mg (3000 μg) per day for adults. No maximum value for carotenoids is defined.
In the Swiss Food Composition Database the retinol content is expressed in micrograms (μg) and two calculated values of vitamin A are listed, taking into account retinol, beta carotene and other carotenoids expressed in micrograms of retinol equivalent (μg-RE):
Vitamin A RE (retinol equivalent, given in μg-RE) = 1 x retinol (μg) + 1/6 x beta carotene equivalent (μg-BCE). This formula (FAO/WHO, 1967) probably overestimates the vitamin activity of beta carotene and other carotenoids, but is that employed in the FDHA Ordinance on the Addition of Vitamins, Minerals and other Substances to Foodstuffs (AVMO, RS 817.022.32, Annex 1, status 1 July 2020) and by the FSVO for the nutrient reference values for Switzerland.
Vitamin A RAE (retinol activity equivalent, given in μg-RE) = 1 x retinol (μg) + 1/12 x beta carotene equivalent (μg-BCE). This formula was published by the US Institute of Medicine in 2001. This is a formula recognised by certain foreign public health authorities.
Vitamin A values are occasionally also listed in International Units (IU). The following conversion factors then apply: 1 IU ≙ 0.3 μg-RE or 1 μg-RE ≙ 3.3 IU
Beta carotene and beta carotene equivalent
Beta carotene is a fat-soluble provitamin which is found in almost all plants, principally in yellow, orange and green fruits and vegetables. In the body it can be converted into vitamin A.
The Swiss Food Composition Database lists the content of beta carotene in μg as well as the content of beta carotene equivalent, expressed in μg-BCE and calculated by taking into account other carotenoids having a vitamin A activity, such as alpha carotene. As data on the various carotenoids is often absent, the equivalent beta carotene content is often underestimated and is identical to the beta carotene content.
The beta carotene equivalents are calculated as follows: Beta carotene-Equivalent (μg-BCE) = 1 x beta carotene (µg) + 0.5 x other provitamin A carotenoids with vitamin A activity (µg)
Vitamin B1 (Thiamine)
Vitamin B1 is a water-soluble vitamin and is found in animal as well as vegetal foodstuffs.
According to the nutrient reference values for Switzerland the requirements for thiamine depend on the energy intake, and for men and women amount to 0.1 mg per MJ and per day. No tolerable upper intake level has been defined.
Vitamin B2 (Riboflavin)
Vitamin B2 is a water-soluble vitamin and is found in both animal and plant foodstuffs. As a result of its intense colour, Riboflavin is added to many foodstuffs as a colorant – declared as E101 colorant.
According to the nutrient reference values for Switzerland, men and women require 1.6 mg per day. No tolerable upper intake level has been defined.
Vitamin B6 (Pyridoxine)
Vitamin B6 is a water-soluble vitamin and is found in both animal and plant foodstuffs.
According to the nutrient reference values for Switzerland, women require 1.6 mg, men 1.7 mg per day. The tolerable upper intake level is considered to be 25 mg per day.
Vitamin B12 (Cobalamine)
Vitamin B12 is a water-soluble vitamin and is found in foodstuffs of animal origin. Foodstuffs of vegetal origin may sometimes contain vitamin B12, but are not considered as reliable sources. A specific glycoprotein of the stomach, the “Intrinsic Factor” is required for its absorption in the intestines.
According to the nutrient reference values for Switzerland, the daily requirement for vitamin B12 is 4 μg for both men and women. There are no known risks of overdose.
Niacin
Niacin (previously also known as vitamin B3 or PP) includes nicotinic acid and nicotinamide. Niacin is a water-soluble vitamin of the B-group and is found in both plant and animal foodstuffs.
According to the nutrient reference values for Switzerland the requirements for niacin depend on the energy intake, and for men and women amount to 1.6 mg-NE (mg-Niacin Equivalent) per MJ and per day. The safe upper intake level for an adult is considered to be 900 mg in the form of nicotinamide and 10 mg in the form of nicotinic acid.
The niacin requirement is supplied not only from the intake of niacin but also from the body’s own synthesis (in the liver and kidneys) from the essential amino acid tryptophan. 1 mg of niacin can be formed from approx. 60 mg tryptophan (= 1 mg Niacin Equivalent). The contribution from the amino acid tryptophan to meet the niacin requirement is not considered in the Swiss Food Composition Database.
Folate
Folate is a water-soluble vitamin of the B-group and is found in both plant and animal foodstuffs. Folate is ingested considerably better from animal foodstuffs than from plant sources.
Folic acid is the name for the synthetic form of this vitamin, which is used for manufacturing fortified foodstuffs or for vitamin supplements.
According to the nutrient reference values for Switzerland, both women and men require 330 μg per day. The tolerable upper intake level of synthetic folic acid for an adult is considered to be 1000 μg per day.
Pantothenic acid
Pantothenic acid (previously known as B5) is a water-soluble vitamin of the B-group and exists in virtually all foodstuffs.
According to the nutrient reference values for Switzerland, men and women require 5 mg pantothenic acid per day. No tolerable upper intake level has been defined.
Vitamin C (Ascorbic acid)
Vitamin C is a water-soluble vitamin and is found exclusively in plant foodstuffs.
According to the nutrient reference values for Switzerland, women require 95 mg vitamin C per day; men require 110 mg. No tolerable upper intake level has been defined.
Vitamin D (Calciferol)
Vitamin D is a fat-soluble vitamin and includes the forms vitamin D2, vitamin D3, 25(OH)D3 and 1,25(OH)2D. The most important representative is vitamin D3 (= cholecalciferol) that is found only in animal foods. Humans are able to synthesise vitamin D3 themselves with the aid of UV-B light.
According to the nutrient reference values for Switzerland, men and women require 15 to 20 μg (600 – 800 IU) of vitamin D per day (foodstuffs, supplements, endogenous production). The safe upper intake level is considered to be 100 μg (4000 IU) per day.
The Swiss Food Composition Database shows the total value of vitamin D activity, including vitamin D3, D2 and, for a small number of foods (e.g. eggs), 25(OH)D3. 25(OH)D3 has a higher metabolic efficiency than the other forms of vitamin D. However, in the absence of sufficient scientific evidence and international consensus, 25(OH)D3 is considered here to be of equal value to other forms of vitamin D. Because of the limited data on 25(OH)D3 content and the failure to take account of the greater efficacy of 25(OH)D3, total vitamin D activity is sometimes underestimated here.
| 1 μg Vitamin D = | 1 μg Vitamin D2 (ergocalciferol) 1 μg Vitamin D3 (cholecalciferol) 1 μg 25(OH) Vitamin D3 |
Vitamin D values are occasionally also listed in International Units (IU). The following conversion factors then apply: 1 IU ≙ 0.025 μg or 1 μg ≙ 40 IU
Vitamin E
Vitamin E is a fat-soluble vitamin which is mainly found in vegetal foods.
According to the nutrient reference values for Switzerland, women require 11 mg vitamin E, in the form of alpha-tocopherol, per day; men require 13 mg. The safe upper intake level for an adult is considered to be 300 mg per day.
Vitamin E exists in the form of diverse tocopherols and tocotrienols, but only alpha-tocopherol is considered to be physiologically active.
The Swiss food composition database indicates the values for vitamin E (in mg) exclusively in the form of alpha-tocopherol. Certain values, however, may still include other tocopherols, meaning that they are slightly overestimated.
Vitamin E values are occasionally also listed in International Units (IU). The following conversion factors then apply: 1 IU ≙ 0.67 mg or 1 mg ≙ 1.49 IU
Sodium (Na)
Sodium is a mineral substance. Sodium occurs naturally in almost all foods and is frequently added – mainly through the addition of sodium chloride (table salt or cooking salt).
According to the nutrient reference values for Switzerland, an adequate intake of sodium for both men and women is 2000 mg per day. This corresponds to about 5 g of salt. No tolerable upper intake level has been defined.
Salt (Sodium chloride, NaCl)
The Ordinance on Information on Foodstuffs (FoodO, SR 817.022.16, status: 19.11.2019) requires the salt content to be indicated on the nutritional label. Consequently, the salt content of foodstuffs is also shown in the Swiss Food Composition database. It is calculated on the basis of the sodium content according to the following formula: salt content (g) = sodium content (g) x 2.5.
Potassium (K)
Potassium is a mineral substance. Foods of plant origin are the main sources.
According to the nutrient reference values for Switzerland, an adequate intake of potassium for both men and women is 3500 mg per day.
Chloride (Cl)
Chloride is a mineral substance which is a constituent of table salt or cooking salt (= sodium chloride).
According to the nutrient reference values for Switzerland, an adequate intake of chloride for both men and women is 3100 mg per day.
Calcium (Ca)
Calcium is a mineral substance. Prevalent sources in our cultural area are dairy products and some mineral waters.
According to the nutrient reference values for Switzerland, women, like men, require 950-1000 mg per day. The tolerable upper intake level for an adult is considered to be 2.5 g per day.
Magnesium (Mg)
Magnesium is a mineral substance.
According to the nutrient reference values for Switzerland, women require 300 mg, men 350 mg per day. The tolerable upper intake level from supplements or fortified foodstuffs is considered to be 250 mg per day (in addition to the natural magnesium levels from food).
Phosphorus (P)
Phosphorus is a mineral substance.
According to the nutrient reference values for Switzerland, women, like men, require 550 mg per day. No tolerable upper intake level has been defined.
Iron (Fe)
Iron is a trace element and exists in two forms: haeme-iron and non-haeme-iron, wherein haeme-iron can be more efficiently assimilated. The principal sources of haeme-iron are meat and fish. Eggs and dairy products contain mainly non-haeme-iron, and vegetal foodstuffs contain exclusively non-haeme-iron.
According to the nutrient reference values for Switzerland, women require 11 to 16 mg, men 11 mg per day. No tolerable upper intake level has been defined.
Iodine (I)
Iodine is a trace element that is present only in very minor quantities in the majority of foodstuffs. The supply of iodine for the Swiss population cannot be ensured through nutrition, which is why the use of iodised table salt (25 mg/kg) is recommended.
According to the nutrient reference values for Switzerland, both women and men require 150 μg per day. The safe upper intake level is considered to be 600 μg per day.
The iodine content of a processed foodstuff such as cheese, bread, sausages or cold meat depends strongly on whether or not iodised table salt has been added. The individual iodine content of a salted product may therefore differ from the indications in this database.
Zinc (Zn)
Zinc is a trace element.
According to the nutrient reference values for Switzerland, the intake of zinc has to be adapted to the phytate content of the food. Depending on the phytate intake levels of 300, 600, 900 or 1200 mg per day, recommended intake levels are 7.5, 9.3, 11 and 12.7 mg per day for women and 9.4, 11.7, 14 and 16.3 mg per day for men. The tolerable upper intake level for an adult is considered to be 25 mg per day.
Selenium (Se)
Selenium is a trace element and is mainly supplied nutritionally by seleno amino acids or their derivatives.
According to the nutrient reference values for Switzerland, women and men require an estimated intake of 70 μg per day. The tolerable upper intake level for an adult is considered to be 300 μg per day.
The selenium content of plant-based foodstuffs differs from region to region and depends on the selenium content of the soil. Swiss soils are poor in selenium. The selenium content of food of animal origin is influenced by the animal feed.