The problem with Group 4 in the food pyramid is thatit only focuses on the protein fraction of each food, without considering thelipid profile and the nutritional value associated with it. Therefore, it doesnot represent the consumption of each individual food on this level correctly. Group 4 consists of fish, beans, meat, poultry, eggs and nuts. The foods onthis level provide protein to the body for growth and repair of cells. They arealso a main source of iron for healthy blood (Abbaspour et al. 2014).The main component in Group 4 appears to be meat.
However, the consumption of meat, especially processed meat, has been shown toincrease the risk of cancer (Sun et al. 2012) type 2 diabetes (Pan et al. 2011) and cardiovascular disease (CVD) (Abete et al. 2014). This is because red and processed meat have highlevels of sodium chloride and saturated fat. The high sodium content increasesblood pressure which leads to the increased risk of CVD. The way meat isprocessed and preserved also affects its impact on health.
For example,nitrates and nitrites are used in the preservation of meat and this increasesblood nitrite concentrations which are related to endothelial dysfunction andatherosclerosis (Kleinbongard et al. 2006). Nuts and beans are also in Group 4. They containfibre, calcium, magnesium, potassium and L-arginine, the precursor amino acidfor nitric oxide (Ros 2010). They are good sources of phenolic antioxidants andtocopherols which protect against LDL oxidation (Hyson et al. 2002).
Nuts are very beneficial against heart disease riskand risk factors. Nuts are also good sources of monounsaturated andpolyunsaturated fatty acids, and they display anti-inflammatory properties (Kris-Etherton et al. 2008). In a cohort study, it was discovered that peoplewith hypercholesterolemia had improved blood vessel dilation and endothelialfunction from a diet containing walnuts (Ros et al.
2004).In Group 4, fish have a wide variety of species tochoose from. All fish contain omega-3 fatty acids which have protective propertiesin preventing CVD, lowering plasma triglyceride levels, reducing thrombosis andarrhythmias, reducing blood clotting and even decreasing the risk of certaincancers (Kris-Etherton et al.
2002). The consumption of oily fish is known to reduce therisk of CVD’s, stroke and heart attack with its cardioprotective properties (Zheng et al. 2012). Fish are low in saturated fat and high in two kindsof omega-3 polyunsaturated fatty acids: docosahexaenoic acid (DHA) andeicosapentaenoic acid (EPA) (Swanson et al. 2012).Although all these foods are a good source of protein,the other nutrient components have been overlooked. These foods have differentnutritional values and should be eaten in different proportions as such.
Fishand plant sources should be the main source of protein in a healthy balanceddiet and should be moved down the food pyramid to be consumed more often. Forexample, nuts and beans should be in Group 1 with the other vegetables, andfish should be in Group 3. For meat, poultry and eggs they should remain in Group 4, however processedmeats should go up a higher level to be consumed less as they contain a lot ofsalt and saturated fats.
A new suggested food pyramid with these changes can beseen in figure 1.