The term “nutraceutical” is derived from the terms nutrition and pharmaceuticals. A food (or part of a food) that provides medical or health benefits, including the prevention and/or treatment of a disease.

Nutraceuticals should not only supplement the diet but also aid in the prevention and/or treatment of disease and/or disorder and should be available in tablet, capsule, and liquid form.

Nutraceutical food sources are all natural and can be classified as:

  • Dietary Fibers

  • Polyunsaturated fatty acids

  • Vitamins

  • Polyphenols

  • Probiotics

  • Prebiotics

  • Herbals/Phytochemicals

Dietary Fibers

Dietary fiber is plant matter that is not hydrolyzed by enzymes secreted by the digestive system, but is digested by the microflora in the gut. Foods rich in soluble fiber include fruits, oats, barley, and beans.

The soluble components of dietary fiber delay gastric emptying of the stomach, thanks to their bulking and viscosity-producing ability. This, in turn, affects the speed of digestion and the intake of nutrients, creating a feeling of satiety. Soluble fiber has been shown to selectively lower serum LDL cholesterol and improve glucose tolerance. It also increases insulin receptor binding and improves glycemic response. Dietary fiber in the colon increases stool volume due to increased water retention, increased transit time, and fecal bacterial mass caused by soluble fiber fermentation. Compared to those with minimal fiber intake, people who consume plenty of dietary fiber are less likely to have stroke, hypertension, diabetes, and gastrointestinal problems.

Polyunsaturated fatty acids (PUFAs)

Also known as essential fatty acids, they do not exist in the body and must be obtained from the diet. PUFAs have two subdivisions: omega-3-(n-3) fatty acids and omega-6-(n-6) fatty acids.

The main omega-3-fatty acids are α-linolenic acid (ALA), eicosapentanoic acid (EPA), docosahexanoic acid (DHA). EPA and DHA are mainly found in oily fish such as mackerel, salmon, herring, trout,

bluefin tuna, and fish oils. Major sources of ALA are mostly flaxseed, soybean, canola, some nuts (eg walnuts) and red/black currant seeds.

Omega-6-PUFAs are mainly composed of linoleic acid (LA), γ-linolenic acid (GLA), and arachidonic acid (ARA). LA occurs mainly in vegetable oils; corn, safflower, soybean and sunflower. ARA is found in animal products such as meat, poultry, and eggs.

Studies show that omega 3 fatty acids are antiarrhythmic (preventing or alleviating irregularities in the heart’s strength or rhythm), hypolipidemic (promoting the reduction of lipid concentrations in the serum), and antithrombotic (reducing atherosclerosis).

Probiotics

Probiotic can be defined as a live microbial supplement that, when given in sufficient amount, affects the body positively by improving the intestinal microbial balance.

Probiotics are usually derived from Lactobacillus and Bifidobacteria strains.

Specific probiotics are often used to treat gastrointestinal (GI) conditions such as lactose intolerance, acute diarrhea, and antibiotic-related side effects. Probiotics are non-pathogenic, non-toxic, gastric acid-resistant agents. There is evidence that probiotics reduce the risk of systemic conditions such as allergies, asthma, cancer, and other ear and urinary tract infections.

Prebiotics

Consumption of prebiotics generally promotes Lactobacillus and Bifidobacterial growth in the gut, thus aiding metabolism. The health benefits of prebiotics include improved lactose tolerance, antitumor properties, neutralization of toxins and stimulation of the intestinal immune system, reduction of constipation, blood lipids and blood cholesterol levels.

Selenium

Selenium is an important trace element that plays a role in the defense against the toxicity of reactive oxygen species, the regulation of the redox state of cells and the regulation of thyroid hormone metabolism.

Vitamins

Compounds such as vitamin C, vitamin E, carotenoids, letuin, and zeaxanthin are collectively known as antioxidant vitamins. These vitamins can cause cancer, cardiovascular diseases, cataracts, etc. It acts both alone and synergistically to prevent oxidative reactions leading to various degenerative diseases including These vitamins are abundant in many fruits and vegetables and exert their protective effects through free radical scavenging mechanisms.

Polyphenols

Polyphenols constitute a large group of phytochemicals produced as secondary metabolites to protect plants from photosynthetic stress and reactive oxygen species. The most important are flavonols, flavones, flavanones and anthocyanins. The polyphenols most commonly found in foods include flavonoids and phenolic acids. Dietary polyphenols are of interest today because studies have suggested that they may have anticarcinogenic and anti-atherogenic effects.

Apart from these, polyphenols also have antioxidant, anti-inflammatory, antimicrobial, cardioprotective activities and play a role in the prevention of neurodegenerative diseases and diabetes.

https://link.springer.com/article/10.1208/ps050325

https://link.springer.com/article/10.1007/s13197-011-0269-4