What is a dietary food, and how is it defined?
The term“dietary food” refers to products designed to meet specific nutritional needs: weight management, blood sugar control, sports nutrition, or medically prescribed diets. In Europe, Directive 2009/39/EC regulates foods intended for special dietary uses, while dietary supplements are subject to Directive 2002/46/EC. In health food stores, dietary foods include meal replacements, foods enriched with specific nutrients (fiber, protein, omega-3), sports nutrition products, and products designed to address digestive discomfort.
What are the key nutrients in dietary foods?
Several families of nutrients form the foundation of dietary foods with documented health benefits:
- Omega-3 fatty acids EPA and DHA: contribute to normal heart function, the maintenance of normal triglyceride levels, and brain function, according to validated EFSA claims.
- Complete plant-based proteins (soy, peas, hemp, brown rice): help meet essential amino acid requirements in vegetarian and vegan diets, which are important for muscle mass and satiety.
- Vitamin C: an antioxidant, it helps protect cells against oxidative stress, supports normal collagen synthesis, and aids in the absorption of non-heme iron from plant-based foods.
- Magnesium: a cofactor in more than 300 enzymatic reactions, it helps reduce fatigue, supports energy metabolism, and contributes to the normal functioning of the nervous system.
Do dietary foods help manage blood sugar levels?
Blood sugar management is one of the main goals of dietary foods for people who are overweight or at metabolic risk:
- Low-glycemic-index foods (legumes, whole grains, oatmeal): slow glucose absorption and limit postprandial insulin spikes.
- Soluble fiber (pectins, guar gum, psyllium): forms a viscous gel in the small intestine that slows down the digestion of carbohydrates. The EFSA claim regarding the reduction of postprandial blood glucose levels by viscous fiber is regulatory-approved.
- Sugar substitutes (erythritol, stevia, xylitol): help reduce carbohydrate intake without a significant impact on blood glucose levels.
How do dietary foods support digestive health?
Dietary foods rich in fiber and probiotics play a key role in maintaining digestive health:
- Dietary fiber (25 to 30 g/day recommended): contributes to healthy bowel function by increasing stool bulk and reducing colonic transit time. The EFSA claim regarding fiber’s contribution to normal bowel function is validated.
- Probiotics (Lactobacillus, Bifidobacterium): as modulators of the gut microbiota, they help maintain a balanced flora, strengthen the intestinal barrier, and help regulate mucosal immunity.
- Prebiotics (inulin, fructo-oligosaccharides): fermentable substrates that selectively feed beneficial bacteria in the microbiota, enhancing the effect of probiotics.
Can dietary foods reduce inflammation?
Certain dietary foods have documented anti-inflammatory properties:
- Omega-3 EPA reduces the synthesis of pro-inflammatory series-2 prostaglandins and leukotrienes, favoring series-3 anti-inflammatory mediators. The EFSA has validated the claim regarding omega-3s’ contribution to a normal inflammatory response.
- Turmeric (curcuminoids): inhibits the NF-kB and COX-2 pathways involved in the production of pro-inflammatory mediators. Incorporating it into standardized dietary supplements with piperine is the most effective approach for bioavailability.
- Polyphenols (resveratrol, anthocyanins from berries, EGCG from green tea): antioxidants that modulate inflammatory signaling pathways and protect cells from oxidative stress.
How do you choose a dietary supplement that suits your needs?
Selecting a suitable dietary supplement depends on several criteria:
- Read the nutritional and health claims: only claims validated by the EFSA and listed in Regulation (EC) No. 1924/2006 are permitted. They ensure a scientific basis for the claimed effects.
- Check the ingredients: the levels of active nutrients, the bioavailability of the forms used, and the absence of unnecessary additives are key quality criteria.
- Tailor the product to the individual’s profile: needs vary depending on age, gender, physical activity, medical conditions, and medications. Medical advice or consultation with a dietitian is recommended for therapeutic diets. Medicinal dietary supplements may require a prescription in certain cases.
