Do we really know what we eat? (II)

Nutritional information is the most important part of food labelling, but it is not always easy to understand the data contained on the label.

At Neolife we try to explain the wide range of concepts included in the nutritional information: portion size, energy value (calories / Kcal), fat content, carbohydrate content, fibre, sodium, calcium, trace elements , daily value or DV%, preservatives and other additives etc.

Tania Mesa – Nutritionist and Nurse from Neolife

Nutritional information area: calories, macronutrients, micronutrients etc.

In a previous article, Do we really know what we eat?, we attempted to shed light on the complex information contained on food packaging. Throughout this article we return to our attempt to teach you how to read and interpret these nutritional labels, in this case by focusing on the Nutritional Information. On most packaging this is the most complex labelling section and the one which provides more information than others.

Nutritional information is only mandatory if the labelling of the product mentions that it has nutritional properties. This consists of:

Serving size

This is defined by the manufacturer. This is a recommendation about the amount of product that should be ingested. This represents what the manufacturer considers to be a “portion”. This typically appears at the top of the label. The quantities usually appear by reference to 100 grams or 100 ml of food.

It is very important to understand that there are products on sale which we usually do not consume a single portion of in one sitting whilst there are others, such as potato chips (crisps), where the portion indicated on the package is usually much smaller than what we actually consume. For example, if we eat two portions of the food stated on the labelling we will be eating twice the calories and nutrients that are indicated.

Do we really know what we eat? Nutritional information

Energy value (calories / Kcal)

The amount of energy that food contains is measured in units called kilocalories (Kcal) or kilojoules (Kj). The indicated calories are equivalent to a portion of food. As a general recommendation, a product that has less than 100 kcal per 100 grams will help us to reduce the caloric density of our diet.

It is worth noting that ‘light’ products may be labelled as light if the product must contains at least 30% less calories than the non-light counterpart.

Fat content

The label indicates the total fat content and identifies the saturated and trans fats. Care should be taken when considering the grams of fat per 100 grams of food as it is recommended that the product does not contain more than 30% fat. However, if you want a diet low in fat then the ideal solution is to choose foods with less than 10 grams of fat per 100 grams of food. Also, where a product indicates a significant fat content this does not mean that we should stop looking at the fat breakdown on the label as a predominance of saturated fats will provide a clear indication of a product that is not good for your health; however, if the fat content is largely unsaturated fats (mostly monounsaturated) and polyunsaturated) this can be beneficial if taken in moderation.

We must not forget to note whether or not the food contains trans fats: if the nutritional information contains hydrogenated or partially hydrogenated vegetable oil then the product contains trans fats.

In general terms a light product will contain less or no fat. However, by eliminating fat from the food, the food can be left without flavour, without consistency. To restore part of that consistency, there are a number of thickening agents that are added to the food: guar gum, carrageenan, xanthan gum etc.

Next we have a table below which shows the total fat content and the saturated fat content in the food:

Total fat content:

  • High total fat content: 20g or more per 100 grams.
  • Moderate total fat content: Between 3 and 20g per 100 grams.
  • Low total fat content: 3g or less per 100 grams.

Saturated fats:

  • High saturated fats content: 5g or more per 100 grams.
  • Moderate total fat content: Between 1 and 5g per 100 grams.
  • Low total fat content: 1g or less per 100 grams.

Carbohydrate content

We can also visualise this content per 100 grams. We advise that the product does not contain more than 10% sugar. If one is unable to determine which are complex carbohydrates (starch) and which are sugars or simple carbohydrates then you should refer to the ingredients and see if the ingredients list sugar, fructose, sucrose or honey. Almost any ingredient that ends in -ose is sugar: dextrose, glucose, lactose, galactose etc. as well as maltodextrin, molasses, high fructose corn syrup, powdered sugar, sweet corn, inverted sugar, maple syrup, syrup, sugarcane juice etc. Any of these names is equivalent to sugar (or worse than sugar in some cases).

Next we have a table below which shows the total sugar content in the food:

  • High sugar content: 10g or more per 100 grams.
  • Moderate sugar content: Between 2 and 10g per 100 grams.
  • Low sugar content: 2g or less per 100 grams.

In addition to calories and macronutrients it is important to consider other nutritional information on the label that will help us achieve a healthy diet. These are:


The fibre content is fundamental because it relates indirectly to the glycemic index of the food, that is to say, how long it will take to digest the food and to raise blood glucose levels. Furthermore, the amount of fibre affects our intestinal health and satiety (fullness).

If the ingredients include words such as polydextrose, inulin or oligofructose, fibre has been added to the product.

Sometimes fibre is broken down on the label into:

  • Insoluble fibre: this is found mainly in whole-grain products (grain-based products), such as bran cereal, wheat, vegetables and fruits.
  • Soluble fibre: mainly found in peas, beans, many vegetables and fruits, oat bran, whole grains, barley, cereals, seeds, rice and some pasta, crackers and other bakery products.

Sodium (salt)

The sodium content in food is of interest to those with cardiovascular problems or those who suffer from hypertension, who must have a low sodium diet. Our society currently uses an excessive amount of salt (principally by manufacturers), to make the products more stimulating to the palate, but this practice can be dangerous. We must take note of the salt content per product and choose only those foods that contain less than 200mg of sodium per 100 grams of food:

  • High content: 1.25g of salt or more per 100 grams / 0.5g of sodium or more per 100 grams.
  • Low content: 0.25g of salt or less per 100 grams / 0.1g of sodium or less per 100 grams.


A product which contains more than 100mg of calcium per 100 grams is considered a “source of calcium”. It is important to keep in mind that for calcium to be properly absorbed by the body it is necessary to also maintain sufficient levels of vitamin D in the body.

Trace elements

These include vitamins and minerals, which are stated on the label if 100g or 100ml of the given product contributes 15% or more of the RDA (Recommended Daily Allowance) when consumed.

Daily value or DV%

This is the % that relates the portion of food to the recommended daily allowance for an individual. The daily values ​​are based on a diet of 2,000 kcal, although your nutritional needs will probably depend on your daily physical activity.

The DV% helps us to determine if a food is high or low in nutrients:

  • High content: If the product provides 20% or more of the daily value.
  • Low content: If the product contains 5% or less of the daily value.

Preservatives and other additives

Additives can be natural or synthetic (chemical) substances that are added to food, not as a result of their nutritional value, but in order to facilitate the conservation of the product, or improve the appearance, taste, colour of the product. That is to say, they are added voluntarily to the food.

One of the biggest problems is that many additives can have more than one name (some up to five and six different names). The most common additives are known by their E prefix (the letter E indicates that it is an additive that is permitted within the European Union) and the number that follows. The permitted additives are classified into different categories according to their functions: if the additive is within the 100 series it is a dye; if it is 200 then it is a preservative; 300 is an antioxidant; 400 is an emulsifier, thickener or stabiliser; 500 is an acidity regulator (PH) or an anti-caking agent; 600 is a flavour enhancer; and 900 brings together several different types, like, for example, sweeteners.

In some cases these additives are necessary and safe to consume. But many others can lead to questions. The following are a particular concern:

  • Monosodium glutamate (MSG) (E621): flavour enhancer. Many studies seem to demonstrate that E621 is toxic; Although the debate is still open so we advise that you attempt to avoid foods that contain E621. Variants of monosodium glutamate, such as monopotassium glutamate (E622) or glutamic acid (E620), may also be found on the label.
  • E133: blue dye, banned in several countries and linked to DNA damage.
  • E124: red dye, also banned in many countries and linked to several types of cancer.
  • E102 (tartrazine): yellow dye, permitted in many countries, but also potentially harmful (linked to depression, migraines, thyroid tumours etc.).
  • Potassium bromate: widely used in baking to provide fluffiness to bread and other products. Although it is banned in many countries due to its high toxicity, the substance can still be found in use elsewhere in the world.
  • Sodium Nitrite / Sodium Nitrate: widely used in the preservation of sausages. The justification for use is that it prevents the formation of botulinum toxin. While some studies indicate that prolonged use is toxic, others claim the opposite is true. What is certain however is that the substance is found naturally in many foods.

Food is a great determinant of our health and the journey begins with the purchase of food that will later be used in the kitchen as we prepare dishes that will be consumed later. Understanding these values, learning to read the list of ingredients and the nutritional labels placed on food products is essential if you are to make an informed purchase. This will help you to read the nutritional information and interpret if it is advisable to purchase the food concerned.