Alkaloids are a large class of organic, nitrogen-containing ring compounds present in plants. They may be toxic at high doses and many have pharmacological effects and are used as medicine or recreational drugs (e.g. morphine, cocaine, caffeine, nicotine). The main alkaloids in vegetables are betalains, capsaicinoids and the glycoalkaloids.
Antioxidants are compounds that prevent or inhibit oxidation of a substance (e.g. vitamin C, vitamin E).
Betalains are water-soluble, nitrogen-containing pigments. The name 'betalain' comes from the Latin name of the common beet (Beta vulgaris), from which betalains were first extracted. There are two subgroups of betalains: (1) the betacyanins that are red to violet, and (2) betaxanthins that are yellow to orange.
The degree to which a nutrient becomes available for use in the body after ingestion.
The process by which osteoclasts (a type of bone cells) break down bone tissue and release minerals resulting in a transfer of calcium from bone fluid to the blood.
The brassica family of vegetables includes broccoflower, broccoli, brussel sprouts, cabbage, cauliflower, kohlrabi, swedes and turnips, plus a range of Asian vegetables including varieties of cabbage, broccoli, bok choy and choy sum. Vegetables from the brassica family all share a common feature; their four-petaled flowers bear the resemblance to a Greek cross, which explains why they are frequently referred to as crucifers or cruciferous vegetables.
Capsaicinoids is the name given to the group of compounds found in members of the capsicum family of plants. They are the compounds which give rise to the heat of chillies and are classified as alkaloids.
A carbohydrate is an organic compound comprising only carbon, hydrogen and oxygen.
Carotenoids are a large family of phytonutrients which provide the yellow, orange and some red colours of plants. They are fat-soluble compounds. Carotenoids belong to a larger class of phytonutrients known as terpenoids. Carotenoids can be broadly classified into two groups: carotenes (alpha-carotene, beta-carotene and lycopene) and xanthophylls (beta-cryptoxanthin, lutein and zeaxanthin).
Cholesterol is a fat-like substance found only in animal foods. Fresh fruits and vegetables contain no cholesterol. Cholesterol is used to produce hormones and cell membranes, and is circulated in the blood plasma of all mammals.
A nonprotein compound necessary for the functioning of an enzyme.
A group of mental processes that includes attention, memory, producing and understanding language, learning, reasoning, problem solving, and decision making.
Consist of a chemical structure that is made up of three or more sugars which are usually linked together to form a chain. Due to their complexity, they take longer to digest and don't raise the sugar levels in the blood as quickly as simple carbohydrates (also known as simple sugars, sucrose, glucose fructose).
Daily Intakes (DIs) are a set of reference values for a variety of nutrients, as well as energy. These nutrients include carbohydrates, sugars, protein, fat, saturated fat, fibre and sodium. The DI values are based on an average adult diet of 8700kJ, which is the daily requirement for an average adult. As different nutrients (carbohydrate, protein, fat and fibre) contribute different amounts of energy, to get 100% of the DI for energy, you need a balance of these nutrients. It is important to remember, that DIs are not recommendations, they simply provide a benchmark suitable for the majority of people. Energy and nutrient intakes vary from person to person depending on gender, age, weight and differing levels of activity. Very active people may have higher requirements, whereas children may have lower requirements.
Diabetes is a metabolic condition characterised by raised blood glucose due to insulin deficiency, insulin resistance or both.
If the effects change when the dose of the nutrient/drug is changed, the effects are said to be dose-dependent.
The ionised or ionisable constituents of a living cell, blood or other organic matter.
A substance produced by a living organism that acts as a catalyst to bring about a specific biochemical reaction. Most enzymes are proteins.
These vitamins cannot be synthesised in adequate amounts by our bodies and must be obtained from food.
ESADDIs are used where for some nutrients where there is insufficient evidence to develop a recommended dietary intake (RDI). RDI is considered a safe intake level.
Fatty acids are a component of fat consisting of a chain of a hydrocarbon with a methyl group at one end and a carboxyl group at the other. The three main types of fatty acids in the diet are saturated, monounsaturated and polyunsaturated.
Flavonoids (also sometimes called bioflavonoids) are phenolics that have a common chemical structure and function as protective phytonutrients in fruits and vegetables. Some of the better known flavonoids include anthocyanins, catechins, quercetin, kaempferol and apigenin.
FSANZ develops food standards for food available in Australia and New Zealand.
A fructan is made up of a chain of fructose molecules. Fructans with a short chain length are known as fructooligosaccharides, whereas longer chain fructans are termed inulins. The longer chain fructans are classed as soluble dietary fibres.
Fructooligosaccharides (FOS), a subgroup of the fructans, are oligosaccharides (carbohydrates) that occur naturally in plants. They are composed of linear chains of fructose units. FOS are not digested and so pass through the human digestive tract largely unaltered. In the colon FOS are utilised by beneficial bacteria and hence are called prebiotics. A healthy microbial population influences digestion and absorption of nutrients, detoxification and elimination processes, and the immune system of the host.
General level health claims are claims about the effect of a nutrient in a food on a health function or a non-serious disease. For example: 'vitamin K supports healthy bones'.
Glucosinolates are sulphur compounds present in brassica vegetables and these compounds are converted to isothiocyanates or indoles by the action of an enzyme called myrosinase. The breakdown products give rise to the pungent and bitter taste of brassica vegetables.
Different carbohydrate foods have different effects on blood glucose levels. The Glycaemic Index (GI) ranks food on a scale from 0–100 according to the effect they have on blood glucose levels. Foods with an index number of 70 or more are considered to be high GI, 55–70 as medium GI and 55 or less as low GI.
Glycoalkaloids are a large group of organic, nitrogen-containing ring compounds present in plants. The alkaloids are a controversial group as they can be toxic at high doses. Although some research indicates some glycoalkaloids may have health benefits they may also have negative impacts on nerve-muscle function and digestive health. However, relatively large amounts need to be consumed to have any negative effect and levels in most vegetables are low. Issues may arise with consumption of green potatoes or large amounts of green tomatoes.
A term used to refer to a molecule connected to sugar molecules. Glycosides tend to exist in plants as a storage form, and upon human consumption they can either be hydrolysed into the molecule and sugars (two separate things) or remain bound together. For example, Cyanidin is a molecule while Cyanidin-3-O-Glucoside is a glycoside thereof that has some unique properties and can be detected in the blood after oral ingestion
High level health claims are claims about the effect of a nutrient in a food that makes reference to a serious disease or biomarker of a serious disease (biomarkers of serious disease include blood cholesterol and blood pressure). For example: 'A diet containing an increased amount of both fruit and vegetables reduces the risk of coronary heart disease.'
A process in which the body's internal environment is kept stable.
Inulin is a carbohydrate belonging to a class of compounds known as fructans and is closely related to fructo-oligosaccharides. Unlike many carbohydrates, inulin is non-digestible. This allows it to pass through the small intestine and ferment in the large intestine.
Isothiocyanates are breakdown products of the glucosinolates. Different glucosinolates produce different isothiocyanates.
The chemical processes that occur within a living organisms in order to maintain life.
Minerals are nutritionally significant elements (elements are composed of only one kind of atom e.g. Fe). Minerals are inorganic, this means they do not contain any carbon atoms. Minerals are comparatively stable under food processing conditions such as heat, light, use of oxidising agents and extremes in pH. Therefore processing does not usually reduce the mineral content. However, minerals can be removed from foods by leaching. Cooking in water can result in some loss of minerals since many minerals have significant solubility in water. In general, boiling vegetables in water causes greater loss of minerals versus steaming them.
A type of unsaturated fatty acid in which there is one double bond. Dietary sources include olives, olive oil, canola oil, peanuts, peanut oil, almonds, avocados, meat from grass-fed animals, and some margarines and spreads.
Chemicals that transmit signals from a neuron (nerve cell) to a target cell across a synapse (synapses are the means by which the signal is passed).
A nutrient is a substance that is required for growth or metabolism of living creatures. Plants absorb nutrients mainly from the soil in the form of minerals and other inorganic compounds, and we obtain nutrients from foods that we eat. Nutrients needed in very small amounts are called micronutrients and those that are needed in larger quantities are called macronutrients. The effects of nutrients are dose-dependent and shortages are called deficiencies. A nutrient is said to be 'essential' when it must be obtained from food, either because we cannot synthesise it or our body cannot produce sufficient quantities. Essential nutrients have a recommended dietary intake (RDI). Nutrients are used to build and repair tissues, regulate body processes and are converted to and used as energy. Nutrients include carbohydrates, fats, proteins (or their building blocks amino acids), vitamins and minerals. In addition to nutrients there are numerous other dietary compounds that promote health by enhancing quality of life or extending lifespan by reducing disease risk. Those compounds that are produced by plants are called phytonutrients.
Nutrient content claims tell you about the nutritional property of a food. These claims can indicate the presence or absence of a particular nutrient in the food and they can also indicate the amount.
The NIP provides information about core nutrients (i.e. energy, protein, fat, saturated fat, carbohydrate), vitamins and minerals in food. The NIP must be presented in a standard format which shows the average amount per serve and per 100g. Information can also be presented on Daily Intakes (DI) and Recommended Dietary Intakes (RDI). FSANZ Standard 1.2.8 (Nutrition Information Requirements) prescribes when nutritional information must be provided, and the manner in which such information is provided.
The state of a person's health in terms of the nutrients in his or her diet.
Type of bone cell that removes bone tissue by removing its mineralised matrix and breaking up the organic bone. The process is known as bone resporption.
Phenolics are one of the main groups of secondary metabolites in plants. The amount and composition of phenolics varies between plants. One of the most commonly talked about groups are the flavonoids but there are also phenolic acids and lignans present in vegetables.
There are four classes of phytoestrogens found in plants: isoflavones, lignans, coumestans and resorcylic acid lactones. The most important dietary phytoestrogens are the isoflavones (although these are not present in vegetables with the exception of alfalfa sprouts) and, to a lesser extent, the lignans. Phytoestrogens have been shown to have a protective effect against the hormone related cancers, such as breast cancer, prostate cancer, bowel cancer, uterine and cervical cancers. They may also have benefits for heart and bone heath. At present no health claims are permitted for phytoestrogens and further human trials are required to substantiate its benefits.
The term phytonutrients simply means plant compounds. It is commonly used to refer to the non-nutrients in plant-based foods that provide an array of health benefits, and in particular the plant pigments. Thus, brightly coloured fruits and vegetables are usually rich in phytonutrients, although there are exceptions. There are thousands of different phytonutrients that have been found in plant foods and no doubt more will be discovered. These protective plant compounds are an emerging area of nutrition and health, with new research reported every day. Two of the most common groups of phytonutrients are carotenoids and phenolics (which include flavonoids). There is also a vast array of other compounds including glucosinolates/isothiocyanates, allium sulphur compounds, chlorophyll, saponins, monoterpenes and capsaicinoids. While phytonutients are not essential dietary nutrients like vitamins and minerals, they contribute to the beneficial health effects which are linked with eating plant foods. Antioxidant activity has been the primary mechanism of action for phytonutrients that has been investigated in recent years. However, the emerging consensus is that although they are radical scavengers in vitro they do may not function as antioxidants in our body. There are many possible mechanisms of action for phytonutrients to provide health benefits, including appropriate regulation of inflammation, neuroprotective effects, enhancement of immune responses, boosting of phase 2 antioxidant enzymes, and regulating energy metabolism and gut health.
Polyacetylenes form a distinct group of chemically reactive natural products, and more than 1400 different polyacetylenes and related compounds have been isolated from higher plants. They are widely distributed in the families Apiaceae (formerly Umbelliferae). Polyacetylenes are toxic at high levels but at the levels they are normally present in vegetables they may have health benefits. The main polyacetylenes in carrots are falcarinol and falcarindiol.
Polyphenolics is the term used for phenolics with more than one phenol ring in its structure. Flavonoids are one common group of polyphenolics.
A polyunsaturated fatty acid is an unsaturated fatty acid with two or more double bonds. Dietary sources include most plant oils, particularly sunflower, soybean, safflower and corn, as well as most margarines and spreads.
The average daily dietary intake level that is sufficient to meet the needs of nearly all (97–98%) healthy individuals in a particular life stage and gender group, including a margin of safety.
The way that the recommendation for vitamin A intake is expressed (micrograms of retinol equivalents). RE accounts for the conversion of carotenoids, such as beta-carotene, to retinol.
A fatty acid in which there are no double bonds between the carbon atoms of the fatty acid chain. Diets high in saturated fatty acids increase the risk of atherosclerosis and coronary heart disease. Found in animal products such as milk, cream, butter, cheese and meat, but they can also be obtained from palm and coconut oil (used in manufactured foods such as pies, biscuits, cakes and pastries).
All terpenoids are synthesised from two five-carbon building blocks. Based on the number of the building blocks, terpenoids are commonly classified as monoterpenes (C10), sesquiterpenes (C15), diterpenes (C20), and sesterterpenes (C25). Carotenoids are one of the main casses of terpenoids present in vegetables and there are also saponins and monoterpenes.
The highest average daily nutrient intake level likely to pose no adverse health effects to almost all individuals in the general population. As intake increases above the UL, the potential risk of adverse effects increases.
Vitamins are organic (carbon-containing) compounds necessary for normal cell function, growth, and development. There are 13 B28 These vitamins are: biotin, folate (folic acid), niacin, pantothenic acid, riboflavin, thiamine, vitamin A, vitamin B6, vitamin B12, vitamin C, vitamin D, vitamin E and vitamin K. Fat-soluble vitamins are stored in our body's fatty tissue. The four fat-soluble vitamins are vitamins A, D, E, and K. The remaining nine vitamins are water-soluble and apart from vitamin B12 and our body does not store them so they must be consumed regularly. Excess water-soluble vitamins leave the body through the urine (hence there is limited value in consuming large amounts in supplements). Some vitamins are more stable (less affected by cooking/processing) than others. Water-soluble vitamins (B-group and C) are more unstable than fat-soluble vitamins (K, A, D and E) during cooking, food processing and storage. The most unstable vitamins include: folate, thiamin and vitamin C. More stable vitamins include: niacin, vitamin K, vitamin D, biotin and pantothenic acid.