Fat and Cholesterol
Maria A. Fiatarone Singh, John Sutton Chair in Exercise, Nutrition, and the Older Woman, 2000
Fatty acids are small units of fat that are used as building blocks, at least in part, of larger molecules such as triglycerides, phospholipids, cholesteryl esters, and in the case of arachidonic acid, the synthesis of biologically active compounds. Individual fatty acids are composed of chains of carbon atoms combined with hydrogen atoms, a methyl group at one end and carboxyl (acid) group at the other. These carbon atoms are linked together by either a single or double bond. The presence of a double bond limits the number of hydrogen atoms that can bind to the carbon atom. If all the carbon atoms are linked together by a single bond, the fatty acid is referred to as a saturated fatty acid (saturated with respect to the amount of hydrogen that can potentially combine with the carbon). If there are one or more double bonds in the chain of carbon atoms, the fatty acid is referred to as unsaturated. Unsaturated fatty acids are frequently divided into two groups: monounsaturated, having one double bond, and polyunsaturated, having two or more double bonds. There are multiple ways to classify fatty acids, many of which are in common usage. The following are descriptions of the systems most frequently used.
Consumption of Foods, Food Groups, and Cardiometabolic Risk
Nathalie Bergeron, Patty W. Siri-Tarino, George A. Bray, Ronald M. Krauss in Nutrition and Cardiometabolic Health, 2017
Traditionally, the cardioprotective effect of fish has been explained by the rich amounts of polyunsaturated fatty acids (PUFA) found in fish, especially omega-3 fatty acids such as eicosapentaenoic and docosahexaenoic acid. As discussed further in Chapter 10, the physiological benefits of these fatty acids are numerous and act through various molecular pathways to lower inflammation and maintain vascular function (Mozaffarian and Wu 2011). Furthermore, various studies have indicated that omega-3 fatty acids decrease the risk of cardiac arrest, reduce blood pressure, improve the lipid profile, and decrease platelet aggregation (Dyerberg et al. 1978, Kris-Etherton et al. 2002, Nestel 1990, Siscovick et al. 1995). Nonetheless, Rizos et al. (2012) concluded in a meta-analysis of 20 clinical trials of 68,680 patients that fish oil supplementation conferred no significant benefit for total CVD, CVD subtypes, or all-cause mortality. Similarly, Chowdhury et al. (2012) found a significant protective effect of fish in epidemiologic studies, but no benefit of omega-3 supplementation in randomized trials.
Healing the Heart with Whole Foods and Food Bioactives
Stephen T. Sinatra, Mark C. Houston in Nutritional and Integrative Strategies in Cardiovascular Medicine, 2015
Select whole foods provide the essential fatty acids include nuts, seeds, nut and seed oils, leafy greens, algae and fish oils. Foods high in naturally occurring omega-6 PUFAs such as nuts, and in particular, walnuts, have been shown to be cardioprotective.169,170 The different components of flaxseed, such as the a-linolenic acid-rich oil and the lignans, may each have cardioprotective effects. Fukumitsu et al.171 found that 100 mg of the flaxseed lignan (secoisolariciresinol diglucoside) was effective at reducing blood cholesterol and hepatic enzymes in moderately hyper-cholesterolemic men. Both flaxseed oil and fish oil supplementation have been shown to increase longer chain omega-3 fatty acids in red blood cell membranes,172 and flaxseed oil incorporation into the diet at 8 g/day for 12 weeks resulted in reduced blood pressure in dyslipidemic subjects compared to a high linoleic acid diet.173 Omega-3 fatty acid supplementation may be useful for primary prevention of CVD167; however, a recent large meta-analysis174 indicated that there was no demonstrable effect for secondary prevention, a finding which is quite opposed to conclusions from previous studies.167
A conjunctive lipidomic approach reveals plasma ethanolamine plasmalogens and fatty acids as early diagnostic biomarkers for colorectal cancer patients
Published in Expert Review of Proteomics, 2020
Tong Liu, Zhirong Tan, Jing Yu, Feng Peng, Jiwei Guo, Wenhui Meng, Yao Chen, Tai Rao, Zhaoqian Liu, Jingbo Peng
Lipids, as hydrophobic biomolecules distributed in living organisms, play an essential role not only in cellular membrane structures and physiological processes but also in signal transduction. There are rapidly increasing evidences proving that disorders of lipid composition and metabolism are found in cancer cells. Phospholipids, composed of sphingomyelins and glycerophospholipids, are a class of lipids that act as major components of cell membranes. It has been reported that bioactive phospholipids, including lysophosphatidylcholine (LPC), ceramide-1-phosphate (C1P), lysophosphatidic acid (LPA), and sphingosine-1-phosphate (S1P) are important mediators that regulate key signals in cancer [1–3]. Fatty acids, a family of molecules characterized by their carbon chain lengths and unsaturated numbers, serve as a synthetic pathway for most lipids. In the past decades, fatty acid metabolism has attracted considerable attention due to its association with various human malignancies [4]. In other words, disruption of lipid synthesis and metabolism has been correlated with proliferation, differentiation, and metastasis in various cancers, including lung, breast, liver, and colorectal cancers.
Omega-3 polyunsaturated fatty acids focusing on eicosapentaenoic acid and docosahexaenoic acid in the prevention of cardiovascular diseases: a review of the state-of-the-art
Published in Expert Review of Clinical Pharmacology, 2021
Yasuhiro Watanabe, Ichiro Tatsuno
Fatty acids are essential not only as an energy source and structural components of cells, tissues and organs, but also for the synthesis of certain biologically active substances. Fatty acids are classified into saturated fatty acids that have no double bonds and unsaturated fatty acids possessing double bonds. Fatty acids with multiple double bonds are called polyunsaturated fatty acids (PUFAs). The PUFA status has been associated with obesity, metabolic disease, cardiovascular and immune functions, insulin action, neuronal development, and neuropsychiatric disorders. PUFAs with double bonds starting at the sixth position from the methyl end of the fatty acid are called omega-6 series, and PUFAs with double bonds starting at the third position are called omega-3 series. These PUFAs are taken up by the cell membrane. Omega-6 PUFAs, represented by arachidonic acid (AA), are the main component of phospholipids in cell membranes and are important for maintaining the function of eicosanoid production. Linoleic acid (LA), an omega-6 PUFA, and alpha-linolenic acid (ALA), an omega-3 PUFA, are considered essential fatty acids because they cannot be synthesized by humans. ALA, a plant-derived omega-3 fatty acid, has been shown in a number of clinical trials to have favorable effects on the cardiovascular (CV) system [1–8], and these findings are supported by basic research demonstrating anti-atherosclerotic and vascular effects [9–11]. In addition, the cardioprotective and antiarrhythmic effects of ALA have recently been reported [12,13].
Fatty acid metabolism in the host and commensal bacteria for the control of intestinal immune responses and diseases
Published in Gut Microbes, 2020
Koji Hosomi, Hiroshi Kiyono, Jun Kunisawa
Fatty acids containing carbon chains of 16 or more are generally referred to as long-chain fatty acids. Long-chain fatty acids are divided into saturated fatty acids, which have no double bonds in their carbon chains, and unsaturated fatty acids, which have double bonds. Palmitic acid is the most common saturated fatty acid found in our body and is provided from endogenous synthesis and diet.20 As the name indicates, palmitic acid is contained in palm oil, but it is also found in meat, dairy products, breast milk, and other sources. Palmitic acid occurs in membrane phospholipids and adipose triacylglycerols and has multiple fundamental biological functions at the cellular and tissue levels. Therefore, disruption of palmitic acid homeostasis leads to several pathophysiological consequences, including tumor growth, metabolic disorder, and inflammation.20
Related Knowledge Centers
- Biochemistry
- Carboxylic Acid
- Chemistry
- Cholesteryl Ester
- Diet
- Ester
- Phospholipid
- Triglyceride
- Aliphatic Compound
- Branched-Chain Fatty Acid