Regulatory Aspects of Human Milk Oligosaccharides

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Human milk oligosaccharides are key components of human milk and appear in various compositions and concentrations in all human milks. In regulatory sense human milk oligosaccharides are classified as novel foods or novel food ingredients requiring safety assessment. In addition, if any health messages are intended to be used also health claim regulations apply. This chapter reviews the regulatory settings and studies human milk oligosaccharides are required to fulfill to be able to enter markets in European Union or United States or elsewhere. Examples include Lacto-N-neotetraose and 2-fucosyllactose with safety assessment in European Union and United States.



Human milk oligosaccharides (HMOs) are a group of sugars which are structurally diverse unconjugated glycans. They are found in human milk with a composition unique to each lactating mother [1]. They have not been used in any other foods previously, and, therefore, the supplementation of HMOs to our food requires both safety assessments and most likely assessment of potential health benefits, too [2–5].

While HMOs have been shown to have an impact on the development of infant gut microbiota, it is not well known if HMOs also already affect human milk microbiota composition or microbiota in oral, nasopharyngeal, gastrointestinal, and urinary tract areas [6, 7]. However, they do have a role in the early colonization of infant gut, and also a modifying and potentially protecting role specific to the mother and infant during pregnancy and breastfeeding [8]. HMOs are currently regarded as new ingredients for infant formulas, other foods, and food supplements. Such consideration involves specific regulatory steps, which are in process in several countries and regions.

Issues pertaining to novel HMOs have increased rapidly due to the fast-paced research on the impact HMOs and the possibility of their larger-scale production. HMOs represent novel tools to modulate the gut microbiota and thus potentially provide health benefits for infants, children, and adults. Such food ingredients are in demand as the importance of the gut microbiota on health has been stressed. HMOs could be considered as prebiotics, and specific components targeted toward unique outcomes and functionalities can be expected to emerge.

Regulatory Framework

In the majority of countries, HMOs are characterized as novel foods in the food regulation, and, therefore, several food authorities require a mandatory safety assessment.

The regulations governing the introduction of novel foods vary by geographical region. In some cases, confusion can result in differentiating novel foods from functional foods, or, as in the European Union, the regulatory category of functional foods is formed by foods with European Commission-approved health claims. The fundamental difference between these two categories of foods is that novel foods must be evaluated based on their safety, whereas foods with health claims need to be evaluated for any desired nutritional, functional, or disease risk reduction claims. Figure 1 demonstrates that the terms are distinct, but sometimes foods and food ingredients fall in both categories, which then necessitate evaluation for both safety and efficacy. The 2-category evaluation in Eu-rope appears most likely for HMOs.

The views and challenges of current legislative framework in the USA, Europe, and some other countries are summarized regarding the assessment of HMOs and their novel food status from the regulatory and scientific viewpoint. Additionally, the possibility of future health claims is discussed.

HMOs are intrinsic components to manipulate the gut microbiota by providing an energy source for beneficial intestinal microbiota and potentially acting as decoy molecules to inactivate potential and opportunistic pathogens in the mucosal surfaces for improving the health of the host. Health-promoting outcomes are in demand as the importance of the gut microbiota in human health has been revealed. The regulations governing the introduction of HMOs vary by geographical region. Novel foods and foods with health claims fall under specific regulations in several countries. The main requirements of the regulations in the EU and USA are similar, but the approval processes differ. There are a number of areas that need to be addressed in any safety assessment of novel food ingredients (NFI).

European Union

Worldwide, the regulations governing novel foods, functional foods, and traditional foods vary. In the EU, the introduction of novel foods that have not been used in the EU prior to May 15, 1997, is currently governed by the Novel Food Regulation (EC) 285/97 [5]. This Regulation clearly defines the risk assessment steps required for any authorization of a novel food prior to the introduction into the EU market. It also defines the concept “substantial equivalence” to commonly used foods, in which case a simplified notification procedure applies. It also defines the role of EU Member States in the approval process. One Member State is responsible for the initial safety assessment of the novel food. Other Member States often challenge the initial assessment, or they ask additional questions related to the safety of novel foods. In these cases, concerns are usually discussed and answered by the European Food Safety Authority (EFSA) committee evaluations. Finally, the authorization decision is made either by the Member State in lead or the European Commission with all Member States involved. In both cases, the authorization is valid allover the EU.

The Novel Food Regulation from 1997 has been under revision and the new regulation steps into force fully from January 2018 onwards. The most relevant change is the transfer to a fully centralized system in the EU. Dossiers are submitted to the European Commission, the EFSA is responsible for the safety assessment, and all authorizations are general, i.e. applicable for everybody without further notification. Changes in the update of the regulation cover also traditional foods from third-world countries. Currently, there is a transition period of 2 years during which the earlier mechanisms are still operable.

Current Regulation until 2018

Based on the current regulation, competent authorities of the member states and the European Commission assess if a food or food ingredient has no history of safe use prior to 1997 in Europe and hence is to be identified as “novel.” The regulation then requires an extensive safety assessment of the food or ingredient prior to acceptance to the EU market [4]. A list of authorized novel foods and NFIs is available in the public registry by the EC. The decisions are explained in an inventory specifying the uses and restrictions for each novel food or novel food component, process, or NFI (http://ec. authorisations/index_en.htm). For bacteria added to foods, which could also be considered novel, there is an annually updated list of microbes intentionally added to foods (QPS, Qualified Presumption of Safety of Microorganisms in Food and Feed), and this list forms the basis of organisms at the species level which are considered safe for foods and feeds in the EU (EFSA 2016 update). Due to their impact on microbiota, human milk oligosaccharide safety assessment may partly be related to microbiota as well.

A novel prebiotic can potentially be a component of conventional foods, food supplements, or foods for particular nutritional uses. Foods incorporating novel ingredients comprise also those designed for specific dietary requirements and may include infant and follow-on formulas, processed cereal-based food, food for special medical purposes, and total diet replacement for weight control.

Current Human Milk Oligosaccharides with Regulatory Decision in the European Union

Until now, 2 HMOs have gone through the novel food safety assessment in Europe with a positive assessment outcome and approval by the European Commission.

2’ - O -Fucosyllactose (2’ -FL) is a synthetic trisaccharide consisting of L-fucose, D-galactose, and D-glucose, which is produced by using L-fucose and D-lactose as starting raw material. The NFI is intended by the applicant to be used in infant and follow-on formulae, foods for special medical purposes for infants and young children, and other foods for infants and young children. The NFI is also intended to be used in foods or food supplements for adults [3].

Lacto-N-neotetraose (LNnT) is a synthetic tetrasaccharide consisting of D-galactose, N-acetyl- D-glucosamine, D-galactose, and D-glucose, which is produced by using
D-lactose as a starting raw material. The NFI is intended by the applicant to be used in infant and follow-on formulae, foods for special medical purposes for infants and young

children, and other foods for infants and young children. The NFI is also intended to be used in foods or food supplements for adults [4].

A third safety assessment evaluation has been made by EFSA for the 2’-O-fucosyllactose in combination with lacto-N- neotetraose as a food supplement for children [5] .

What Did the Member States Question in Case of Human Milk Oligosaccharides?

Several questions were raised by the EU member states following initial safety assessment. These included for example the following:

2’ - O -Fucosyllactose [4]

  • In the dossier, it is stated that the intake of 2’ -FL in the form of food supplements would not be expected to influence the overall daily intake. However, one should consider the possibility for combined intake of 2’ -FL from food supplements and other food uses specified in the dossier as a realistic scenario, which could more or less double the daily intake for high-level users.
  • Considering that the NFI may also be consumed by more vulnerable individuals such as those with conditions that result in a “leaky gut,” any further information could be provided on any possible consequences that may be associated with an increased level of NFI absorption.
  • Intake of large quantities of indigestible carbohydrates may produce laxative effects. As there are no human studies on 2’ -FL, apart from experience with infants who have been breastfed, nothing can be said about the quantities of 2’ -FL which may produce laxative effects.
  • The potential for genotoxicity was only assessed in 2 in vitro tests for mutagenicity. A test for potential clastogenic activity is lacking (in vitro micro-nucleus test or in vitro chromosome aberration test). The absence of geno-toxicity for this 2’ -FL preparation would only be demonstrated sufficiently upon obtaining a favorable outcome in such study. 

     Lacto-N-Neotetraose  [5]

  • Request confirmation that the solvents used are acceptable for food use.
  • The estimated intake for distinct population groups, based on food consumption data from the UK, ranges from 26 to 329 mg/kg body weight per day for the 95th percentile. However, these intake estimates do not include the po-tential additional intake of LNnT from food supplements, as proposed in the application.
  • The intake of large quantities of indigestible carbohydrates can have laxative effects. Since there are not yet any human studies on LNnT other than those with breastfed infants, no statement can be made on what levels of LNnT intake could potentially lead to laxative effects.

Nutrition and Health Claims

The EC regulation on nutrition and health claims 1924/2006 requires that such claims are based on scientific evidence and acceptability. EFSA has provided scientific and technical guidance for presenting applications for health claims on food [9]. Recently, an EFSA guidance document [10] or document on PAR-NUTS Directive 2009/39/EC or EU Regulation 609/2013 indicates that there are no escape routes to circumvent the Health Claims Regulation 1924/2006. Hendriksen and Verhagen [11] have developed a decision tree to discern PARNUTS foods from ordinary foods (with health claims). Following the publication of the Health Claims Regulation 1924/2006, the EFSA has evaluated around 3,000 health claims for scientific substantiation.

United States

In the United States, all foods and food ingredients are regulated under the Food Drug and Cosmetic Act (FDCA). In the USA, the safety of new and novel foods (including HMOs) is primarily the responsibility of the food manufacturer. The regulation states that:

any substance that is intentionally added to food is a food additive that is subject to premarket review and approval by the Food and Drug Administration (FDA), unless the substance is generally recognized, among qualified experts, as having been adequately shown to be safe under the conditions of its intended use.

In the USA, HMOs intended for use in foods other than dietary supplements are regulated under the same regimen as all other food ingredients – that is, they may be introduced as food additives or as GRAS (Generally Recognized as Safe) substances, at the discretion of the manufacturer. There are two other conditions that pertain to GRAS substances. First 

the information demonstrating safety must be generally available to the scientific community, usually regarded as requiring publication in the peer-reviewed scientific literature. Second, there must be general acceptance of the safety of the substances throughout the scientific community – there cannot be significant dispute regarding safety.

The FDA has no fundamental role in GRAS determinations except in an advisory capacity. The law that established GRAS (the 1958 Food Additive Amendment to the FDCA) specifically excluded GRAS substances from requiring FDA review and approval prior to entry into the food supply. The GRAS status of the intended use of a HMO is determined by a panel of qualified scientists who render the opinion that there is a “reasonable certainty of no harm” from the intended use, and further that they believe that other equally qualified scientists would reach the same conclusion. This process may be internal to the company and maintained as confidential to the company and disclosed only to customers under confidentiality.

In 1997, the law was amended to provide for a GRAS notification whereby companies could submit it to the FDA. The submission usually consists of an assessment of existing data by a group of recognized experts. Such safety assessment through scientific procedures requires the same quantity and quality of scientific evidence as is required to obtain approval of the substance as a food additive and ordinarily is based on published studies, which may be corroborated by unpublished studies and other data and information. This is a voluntary submission whereby the FDA reviews the information and the favorable FDA response is “FDA has no questions at this time.”

HMOs have a long history of use in food for infants in human milk. However, the compositions vary, and HMOs are not available in other foods. For new and novel HMOs, the route to market as a dietary supplement is to have GRAS self-affirmed for use in food and then to use it in a dietary supplement in the same form. Such notifications have been provided for the 2’-O-fucosyllactose, 2’ -fucosyllactose, and lacto-N-neotetraose:

2’ -O-Fucosyllactose (Glycom A/S). Intended for use in term infant formula at a maxi-mum level of 2,400 milligrams/Liter. Also intended for use in baked goods and baking mixes, beverages and beverages bases, coffee and tea, dairy product analogs, infant and toddler foods, grain products and pastas, milk (whole and skim), processed fruits and juices, processed vegetables and juices, and sugar substitutes at maximum levels ranging from 0.084 to 2.4 grams/ serving [12].

2’ -Fucosyllactose (Jennewein Biotechnologie, GmbH). For use as an ingredient in infant and toddler formula at a level of not more than 2 grams 2’-fucosyllactose per liter of formula [13]. 

Lacto-N-Neotetraose (Glycom A/S). Intended for use in term infant formula at a max-imum level of 600 milligrams (mg)/Liter. Also intended for use in baked goods and baking mixes, beverages and beverage bases, coffee and tea, dairy product analogs, infant and toddler foods, grain products and pastas, milk (whole and skim), processed fruits and juices, processed vegetables and juices, and sugar substitutes at maximum levels ranging from 0.02 to 1.2 grams/serving [14].


In Japan, the assessment of novelty is based on both the source and the traditional use of foods or food ingredients in Japan. Details on novel HMOs are not available currently.


No applications of HMOs have been handled as of yet (August 2016).

Potential Areas for Health Claim Documentation

Several in vitro and even human studies have been conducted to foresee the potential of HMOs for health claims in Europe and the USA. An example of health claim substantiation is given for probiotics and prebiotics [15]. It is important to remember that the single HMOs and their combinations all form unique products for testing, and thus careful consideration and adjustment are necessary prior to conducting human intervention trials.

The areas of interest have included HMOs and necrotizing enterocolitis, different microbial challenges in the gut, traveller’s diarrhea, and even long-term potentiation of learning capabilities in a rodent model [16–20] .

Summary and Future Perspectives

What is known of HMOs in the regulatory area in the United States and the European Union:

  • In the EU, HMOs are considered novel foods/NFIs with 2 oligosaccharides, and their combination passed through safety assessment.
  • In the USA, 3 HMOs have been passed through according to the GRAS notification system.
  • In the EU, the Novel Food Regulation is updated and will be fully operational in 2018; the approval system will be revised, and new guidance for applications has been set by EFSA.
  • No health claims exist for HMOs in the EU or USA and if applied for these need to be documented for efficacy.
  • The regulatory framework of HMOs varies by geographic region, thus different interpretations on both safety and potential claims could be foreseen.


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