Helper T-cells are a subset of T-cells that assist in coordinating and regulating immune responses. They release signaling molecules to facilitate the activation of other immune cells, including B-cells and cytotoxic T-cells.

Herbal nootropics refer to natural substances derived from plants that are believed to enhance cognitive function, memory, and overall brain health. Unlike synthetic nootropics, these compounds are sourced from traditional medicine systems and are valued for their potential cognitive benefits.

Hidden hunger refers to a form of malnutrition where individuals suffer from deficiencies in essential micronutrients—such as iron, zinc, iodine, and vitamin A—despite consuming adequate energy intake. This often occurs when the diet is energy-dense but lacks essential nutrients, leading to long-term health complications.

High-density lipoprotein (HDL) cholesterol is considered beneficial because it helps remove excess cholesterol from the bloodstream, reducing the risk of heart disease. It is often referred to as “good cholesterol”.

Highly palatable foods are characterized by being high in fat, sodium, simple sugars, and carbohydrates. This term has recently been operationalized within research to lend understanding to the various definitions used historically to denote this term. The new standardized and operationalized definition of highly palatable foods is “hyperpalatable foods” (HPFs) (Fazzino & Rohde, 2019). HPFs meet certain criteria regarding the percentage of fat, sodium, simple sugars, and carbohydrates contained in a food item.

Hippocampal-dependent learning and memory (HDLM) refers to the process of acquiring and retaining information that relies on the proper functioning of the hippocampus. This type of memory encompasses various cognitive tasks, such as spatial navigation and declarative memory (memories of facts and events). HDLM is essential for forming new memories and recalling past experiences, and any dysfunction in the hippocampus can lead to deficits in learning and memory processes.

The hippocampus is the neuroanatomic structure of the limbic system that is thought to be involved in consolidating learning. It is so named because it resembles a seahorse, which is a small structure deep within the brain. The hippocampal complex consists of the hippocampus proper and surrounding structures of the dentate gyrus and the parahippocampal gyrus, all of which are involved in learning and the formation of memory.

The body’s aim to maintain a stable internal environment.

Eating in response to a perceived energy need arising from the body’s homeostatic pathways in the brain signal a physiological depletion of energy stores and results in increased motivation to eat (Lutter & Nestler, 2009).

Homeostatic feeding involves the dietary intake of nutrients and calories needed to survive biologically and meet energy needs (i.e., often referred to as ‘maintaining the body’s homeostatic processes’).