SOURCES: Elaine Turner, PhD, RD, associate professor, department of Food Science and Human Nutrition, University of Florida, Gainesville. Sharon B. Spalding, MEd, CSCS, professor, physical education and health; and associate director, Virginia Women's Institute for Leadership, Mary Baldwin College Staunton, Va. American Dietetic Association web site. Institute of Medicine at the National Academies web site.
The need for efficient detoxification and excretion is greatly increased by environmental pollution from the chemical industry, herbicides and pesticides used by industrial agriculture, antibiotic treatment of animals, transport, and plastic packaging.  In our polluted world, the increased toxic load may be compensated for by an increase in nutrients to promote detoxification. One can respond by taking large doses of supplements of essential nutrients, for example, antioxidants vitamin C and E, and an adequate dose of selenium, which help the body detoxify harmful chemicals. Also helpful is regularly taking sauna baths, fasting periodically, and eating an excellent diet that includes generous portions of dark green leafy vegetables and colorful vegetables and fruits. 
Vitamin C protects the brain and nervous system from damage caused by stress because the synthesis and maintenance of chemical neurotransmitters such as adrenaline and noradrenaline requires adequate levels of vitamin C.  Vitamin C is also needed to repair collagen which is essential for skin, blood vessels, bones and joints, and muscles. When these are damaged by physical stress, extra vitamin C is necessary. A controlled trial of 91 adults who experienced increased anxiety and stress 2-3 months after an earthquake in New Zealand in 2011 was divided into three groups, two were given a broad spectrum supplement of micronutrients in low or higher doses.  The supplements were found to alleviate the experience of stress, with the biggest dose having the biggest effect.
^ Fortmann, SP; Burda, BU; Senger, CA; Lin, JS; Whitlock, EP (Nov 12, 2013). "Vitamin and Mineral Supplements in the Primary Prevention of Cardiovascular Disease and Cancer: An Updated Systematic Evidence Review for the U.S. Preventive Services Task Force". Annals of Internal Medicine. 159 (12): 824–834. doi:10.7326/0003-4819-159-12-201312170-00729. PMID 24217421.
There is more than one way to eat healthfully and everyone has their own eating style. Make healthier choices that reflect your preferences, culture, traditions, and budget. Choose fruits, vegetables, grains, dairy, and protein foods to get the most nutrition and meet your personal calorie needs. Aim for a variety of foods and beverages from each food group and limit saturated fat, sodium, and added sugars.
It's even more important for older people to stay hydrated. Age can bring a decreased sensitivity to thirst. Moreover, it's sometime harder for those who are feeble to get up and get something to drink. Or sometimes a problem with incontinence creates a hesitancy to drink enough. Those who are aging should make drinking water throughout the day a priority.
Use MyPlate (PDF – 281 KB) as a guide to build a healthy diet. Think about filling your plate with foods from the five food groups — fruits, vegetables, grains, proteins, and dairy — at each meal. Snacks can be a good way to fill in fruits and whole grains you might have missed at meals. Most of us don’t need complicated calorie counting programs or special recipes for healthy eating.
In its natural state, sugar is a relatively harmless — even necessary — carbohydrate our bodies need to function. It’s found in fruits, vegetables and dairy as the compound fructose or lactose. The problem comes when sugar is added to foods during processing for added flavor, texture or color. Eating too many of these empty calories has many health effects, the most obvious being major weight gain. Added sugar drives your insulin levels up, messes with your metabolism and causes those calories to turn right into belly fat. Sugar goes by many names. Learn more about the surprising benefits of cutting back on sugar.
^ Siscovick DS, Barringer TA, Fretts AM, Wu JH, Lichtenstein AH, Costello RB, Kris-Etherton PM, Jacobson TA, Engler MB, Alger HM, Appel LJ, Mozaffarian D (2017). "Omega-3 Polyunsaturated Fatty Acid (Fish Oil) Supplementation and the Prevention of Clinical Cardiovascular Disease: A Science Advisory From the American Heart Association". Circulation. 135 (15): e867–e884. doi:10.1161/CIR.0000000000000482. PMID 28289069.
In 2015, the Australian Government's Department of Health published the results of a review of herbal supplements to determine if any were suitable for coverage by health insurance. Establishing guidelines to assess safety and efficacy of botanical supplement products, the European Medicines Agency provided criteria for evaluating and grading the quality of clinical research in preparing monographs about herbal supplements. In the United States, the National Center for Complementary and Integrative Health of the National Institutes of Health provides fact sheets evaluating the safety, potential effectiveness and side effects of many botanical products.