## 3 Nutraceuticals
#### (a) Functional Foods  
When consumed, these foods add value to one's health and contribute to the prevention of diseases such as type 2 diabetes mellitus due to their inherent antioxidant and anti-inflammatory properties [78], which are some of the major underlying mechanisms involved in the development of diabetes, and being able to combat them serves as an option for a better management strategy in the fight against diabetes mellitus. Furthermore, polyphenols, alkaloids, unsaturated fatty acids, vitamins A, B6, B12, C, D, and E, folate, and antioxidants (beta-carotene and lycopene) are among the most prevalent functional foods with noticeable health advantages [79]. One mechanism for postprandial hyperglycemia is the action of alpha-amylase and alpha-glycosidase enzymes in the human stomach, which work by turning food carbs into glucose after meals [52]. As a result, agents that target inhibition of these enzymes would contribute to hypoglycemic states, and phenolics possess this ability by inhibiting \begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & \multicolumn{5}{c}{**Classification of Nutraceuticalticals**} \\ \hline
**Type of** **Nutraceuticaltical** & **Source** & **Active Chemical** & **Mechanism of Action** & **Disease/Illness** & **Reference** \\ \hline
**Phytochemicals** & & & & & \\ \hline Flavanols & Fruits, vegetables, chocolates & Cocoa & Antioxidants, anti-inflammation & Cancer, diabetes mellitus, heart disease, renal problems & [71] \\ \hline Probiotics & & & & & \\ \hline Yogurt, fermented milk & \begin{tabular}{c} Streptococcus \\ thermophilus, \\ Lactobacillus \\ \end{tabular} & Hypoglycemic activities & Diabetes mellitus & [72] \\ \hline Prebiotics & & & & & \\ \hline \hline \end{tabular} \begin{tabular}{c c c c c} \hline \hline \multirow{4}{*}{Postbiotics} & \begin{tabular}{c} Prebiotic \\ microorganisms \\ \end{tabular} & \begin{tabular}{c} CARADA \\ \end{tabular} & \begin{tabular}{c} Anti-hypertensive, \\ antidepressant, anti-diabetic \\ \end{tabular} & \begin{tabular}{c} Neurological disorders, \\ diabetes complications \\ \end{tabular} & [76] \\ \hline \hline \multirow{3}{*}{Synbiotics} & \
\begin{tabular}{c} Products of \\ pre-probiotics \\ \end{tabular} &
\begin{tabular}{c} Reduction in oxidative stress, \\ inflammatory process, \\ gastrointestinal barrier \\ maintenance \\ \end{tabular} & [77] \\ \hline \hline \multicolumn{5}{c}{**Non-Traditional Nutraceuticalticals**} \\ \hline
**Fortified** & & & & \\ \hline \hline \multirow{4}{*}{**Recombinant**} & \begin{tabular}{c} Orange juice enriched \\ with calcium, \\ milk with \\ cholesterol \\ \end{tabular} & Calcium, ascorbic acid & \begin{tabular}{c} Anti-hyperglycaemia, \\ enhance insulin sensitivity \\ \end{tabular} & Diabetes mellitus & [78] \\ \cline{1-1}  & \
\begin{tabular}{c} Iron rice, golden rice, \\ maize, golden mustard, \\ multivitamin corn, \\ gold kiwriruit \\ \end{tabular} &
\begin{tabular}{c} Ascorbic acid, \\ carotenoids \\ \end{tabular} & Enhance immune response & [78] \\ \hline \hline \end{tabular}
\end{table} 
Table 1. _Cont._the enzymatic activity of alpha-glucosidase in the small intestine, as well as antioxidant and anti-inflammatory properties, which all contribute to mechanisms involved in the management and prevention of diabetes mellitus [52]. Millets and seeded grains have been used for decades for their nutritional benefits and subsequently possess active properties with health benefits, including micronutrients (zinc, magnesium, iron), which aid in insulin activity and metabolism. Phytochemicals (flavanols, phenolics), which have antioxidants, anti-diabetic and anti-inflammatory effects, and dietary fiber (soluble and insoluble fibers), delay carbohydrate digestion and absorption as a means of controlling glycemic levels [53]. L-carnitine is derived through dietary sources (such as meat and dairy products) as well as biosynthesis from lysine and methionine [80]. L-carnitine improves insulin sensitivity, decreases insulin resistance, and has lipid-lowering characteristics [54].