Nutritional supplements are products to aid you when you are not getting enough nutrients from your meals. Most common supplements used by people today are multivitamins, protein shakes and meal replacement shakes. In todays times where people are so busy and just don't have the time to sit down to a meal supplements have become then next best thing. These days they have supplements for just about anything from fish oils, Vitamin B or fat burning. While most of these supplements will help you some of them are not good for you. So always consult your doctor first before taking any supplement.
A spokesperson for optimal nutritional intake is the well-known biochemist Bruce Ames, who proposed the "triage theory of nutrients," in which enzymes responsible for cell maintenance functions evolved to have lower affinity for the essential vitamin and mineral cofactors than the enzymes responsible for short-term survival, to preserve life during times of famine. 
I totally agree about attitude – it can really help you or hurt you and is so valuable to pay attention to. I’ve heard the 90/10 idea also presented as the 80/20 rule where you do your absolute best 80% of the time and don’t kill yourself over the 20%. I think this is a healthy way to approach healthy eating and, as long as you’re making those positive choices 80 or 90 percent of the time, you’re probably going to still see results and feel great. I find each day allowing that to sneak up too much for me so I leave one cheat day to get all that out. It’s still a percentage of my overall eating, just on a day, rather than every day. I hope that makes sense!
^ Jump up to: a b c Morton RW, Murphy KT, McKellar SR, Schoenfeld BJ, Henselmans M, Helms E, Aragon AA, Devries MC, Banfield L, Krieger JW, Phillips SM (2017). "A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults". Br J Sports Med. 52 (6): bjsports–2017–097608. doi:10.1136/bjsports-2017-097608. PMC 5867436. PMID 28698222.
A 2013 study on herbal supplements found that many products were of low quality, one third did not contain the active ingredient(s) claimed, and one third contained unlisted substances. In a genetic analysis of herbal supplements, 78% of samples contained animal DNA that was not identified as an ingredient on the product labels. In some botanical products, undeclared ingredients were used to increase the bulk of the product and reduce its cost of manufacturing, while potentially violating certain religious and/or cultural limitations on consuming animal ingredients, such as cow, buffalo or deer. In 2015, the New York Attorney General identified four major retailers with dietary supplement products that contained fraudulent and potentially dangerous ingredients, requiring the companies to remove the products from retail stores.
Dietary supplements are substances you might use to add nutrients to your diet or to lower your risk of health problems, like osteoporosis or arthritis. Dietary supplements come in the form of pills, capsules, powders, gel tabs, extracts, or liquids. They might contain vitamins, minerals, fiber, amino acids, herbs or other plants, or enzymes. Sometimes, the ingredients in dietary supplements are added to foods, including drinks. A doctor’s prescription is not needed to buy dietary supplements.
Nutritional supplements may be designed to provide specialized support for athletes. Some of these consist of high-protein products, such as amino acid supplements, while other products contain nutrients that support metabolism, energy, and athletic performance and recovery. People engaging in intense athletic activity may have increased needs for water-soluble vitamins, antioxidants, and certain minerals, including chromium. Sports drinks contain blends of electrolytes (salts) that the body loses during exertion and sweating, as well as vitamins, minerals, and performance-supporting herbs.