Nutrition Scores

Have you ever wondered how essential nutrients keep you healthy? We want to bring you more digestible nutrition information to your diary using Nutrition Scores. 

Nutrients aren’t eaten in isolation but as a part of the foods that make up your diet. Studies using single nutrients to improve health have generally yielded mixed results. A better approach is to look at nutrient profiles; each Nutrition Score is made up of a group of nutrients that work together to contribute to your health. This gives you the bigger picture view of how your diet is meeting your nutrition goals, while you can still get into the details for each micronutrient target in your Nutrient Targets Summary. 

Nutrition Scores are calculated from how much of each nutrient target and nutrient ratio in the category you have achieved, based on the data available in the foods you have logged to your diary. Reaching your Daily Target for a nutrient maximizes your Nutrition Score, while going over your Maximum Target will reduce your score in that category.

Keep in mind, the Dietary Reference Intakes apply to the healthy general population and are not meant to apply to those who are deficient or in conditions that may cause an increased requirement. If you have customized your nutrient targets to meet your needs, your Nutrition Scores will be calculated from the targets you have chosen. 

For example, our Immune Support score is calculated based on your targets for specific nutrients that support a healthy functioning immune system.  

Nutrition scores are shown in the diary, on your long-term Nutrition Reports, and can even be charted on the Trends > Charts tab. 

You can toggle this area on and off in your diary by visiting the Settings > Display tab. Highlight areas of health that are important to you by choosing up to eight Nutrition Scores to view in your Diary. 

Learn more about each Nutrition Score below, highlighting some of the key roles of micronutrients in maintaining your health: 

• All Targets
• Vitamins 
• Minerals 
• Electrolytes 
• Antioxidants 
• Immune Support 
• Metabolism Support 
• Bone Health 
• Blood Health 
• Oral Health
• Keto Score
• Plant-Based Score
• Women's Health Score
• Men's Health Score
• Data Quality

All Targets

This score summarizes how many of your nutrient targets you have achieved.

Vitamins 

Vitamins are organic molecules (made up of carbon and other elements) that you need in small amounts from foods because your body cannot make them, or not in enough to meet your needs. This Nutrition Score summarizes your overall intake of all micronutrients in the vitamin category.

Minerals 

Essential minerals are elements (meaning they exist on their own, not as part of a larger molecule), like iron, magnesium and selenium, that you need in small quantities in your diet. This Nutrition Score summarizes your intake of your mineral targets.

Electrolytes 

Electrolytes are molecules that have a positive or negative charge that gives them the ability to conduct electricity. Sodium, potassium, calcium and magnesium are essential minerals that have a positive charge and are important electrolytes in your body.

Our cells create concentration gradients, that is a higher concentration of an electrolyte on one side of the membrane and a lower concentration on the other, to store energy. They use this energy to bring nutrients across the cell membrane and control the movement of fluid in your body, both in your blood and inside your cells. Fluid balance is responsible for maintaining your blood pressure. Electrolytes also buffer the pH of your blood so that it does not become too acidic or alkaline. 

The difference in concentration of charged electrolytes also transmit nerve signals in your body through a form of electro-chemical energy. This is the same way that batteries store energy to power electronics. Your brain and nervous system use nerve signals to send and receive information to and from the rest of your body. Electrical signals are also used to trigger your heartbeat and contract your muscles.

Antioxidants 

Free Radicals and Oxidation 

Every cell contains molecules that bump into and interact with one another. These interactions lead to chemical reactions that are responsible for everything that happens in your body; getting the air you breath from your lungs to your cells, digesting the food you eat, your heartbeat, forming a blood clot on a paper cut, sending pain signals when you stub your toe, everything!  

Oxidation is a chemical reaction that describes when a molecule loses electrons. Have you ever seen apple slices turn brown when they are exposed to air? That’s an example of oxidation. Oxygen in the air steals electrons from molecules in the apple and it causes the fruit to change colour. Oxygen is a molecule that is strongly attracted to electrons and is often involved in oxidation reactions. Because you need oxygen to make energy, there is a lot of oxygen around to steal electrons in your cells. 

Most molecules keep an even number of electrons, and really don’t like to have a single electron on its own. When oxygen comes along and steals one, this can start a chain reaction: the molecule with an unpaired electron tries to steal one from a third molecule, which becomes reactive and unstable until it takes an electron from a neighbouring molecule, and so on. When a molecule has an unpaired electron and is looking to find a replacement, it is called a free radical. Like a game of tag, a free radical steals an electron and tags the next molecule ‘it’.   

Oxidation and free radicals are a part of life and your body has ways to remove free radicals and prevent the chain reaction. When a large number of free radicals are formed, they can cause damage; once an apple turns brown you can’t change it back. In your cells, free radicals steal electrons wherever they can – from your proteins, fats, cell membranes, even your DNA. This causes damage to your cells, called oxidative stress, and over time contributes to chronic diseases like cardiovascular disease, cancer and cognitive decline.  

Antioxidant Nutrients 

Antioxidants are a bit like cleaners in the cell. They mop up free radicals by donating one of their own electrons. They are much more stable with an odd number of electrons compared with free radicals, and your body can replenish antioxidants with electrons to break the free radical game of tag. Have you ever put lemon juice on apple slices? Lemons are a great source of vitamin C - an antioxidant - that protects the fruit from browning caused by oxidation. 

Some antioxidants that are water-soluble, like vitamin C and selenium, protect the fluids inside and outside of your cells. Others are fat soluble, like beta-carotene, lycopene and vitamin E. These protect fats inside your cells, your cell membranes, and protect against oxidation of LDL cholesterol.  

Selenium works with an important antioxidant in the cell, called glutathione to neutralize free radicals. It has also restores vitamin C after it has lost an electron, so you can reuse vitamin C to take out more free radicals (1). Riboflavin (vitamin B2) is used to recycle glutathione (2). Other trace minerals, copper, zinc and manganese are used in enzymes called superoxide dismutase, that remove oxygen free radicals.  

While some of the antioxidants are essential nutrients, you can also track other types of antioxidants, called carotenoids, using Cronometer. Carotenoids are in the same family as vitamin A. We can make vitamin A from some of the carotenoids: beta-carotene, alpha-carotene and beta-cryptoxanthin. Lycopene, lutein and zeaxanthin are carotenoids that can’t be used to make vitamin A but are great antioxidants. Lutein and zeaxanthin are found in higher concentration in eyes (3) where they provide protection against oxidative stress caused by light hitting your eyes. There are no dietary reference intakes for the carotenoids; to calculate Nutrition Scores for these nutrients we have used the following values used in clinical trials:   

• Beta-carotene: 15 mg/day (4)  
• Lycopene: 30 mg/day (5)  
• Lutein + zeaxanthin: 12 mg per day (4)  

There are many more compounds in foods that may act as antioxidants, though we don’t have data for them all. It is recommended to eat a variety of plant-based foods, including fruits, vegetables, whole grains, beans and legumes, nuts and seeds to get a good supply of a variety of free radical-fighting substances.  

Immune Support 

Your immune system is what protects your body from disease-causing organisms, bacteria and viruses. It is your body's security system, including multiple lines of defense: walls that prevent entry, an alarm system, first responders and special forces trained to combat repeated attacks. 

There are three main parts to your immune system:  

1. Physical barriers, like your skin and the lining of your intestinal tract. These are the walls and doors that keep intruders from entering your body. 
2.  Innate immunity – When an intruder is found, cells that form your innate immune response are the first on the scene. They sound the alarm to recruit more help through a process called inflammation. Inflammation identifies an injured or infected area so that your body knows where the infection is and what you need to fight it. Innate immune cells also begin the attack against intruders to contain them as best they can.  
3. Adaptive immunity – these defenses respond to infectious agents that your body has seen before. They learn each intruder’s weakness to deliver a quick, targeted attack that is specific to each type of infection. 

Nutrients that Support the Immune System 

Vitamin A, folate, vitamin B12 and zinc keep skin healthy to block pathogens from entering your body. In the security system analogy, these nutrients help maintain the locks on your doors so they can do a better job of keeping intruders from getting inside. 

Intruders do sometimes slip past the door. When they cause damage in your body, an alarm is triggered to bring help. This alarm is inflammation – a normal part of your body’s defense against infection. Omega-3 and omega-6 are types of polyunsaturated fatty acids (PUFAs) that become a part of the cell membrane of immune cells. On the outer surface of the cell, they help relay information into the cell to gather resources to fight an infection (6). They send signals that determine the intensity and duration of an immune response. In general, omega-6 tend to promote the inflammatory response to a greater extent, while omega-3 have a weaker effect, resulting in a less intense response. Keeping your intake of omega-6 in relative proportion with omega-3 helps maintain a more moderate immune response, that helps fight off infection without over doing it. 

Vitamin C and copper are antioxidants that remove reactive compounds that are made when cells are damaged during an infection (7). Vitamin E is another antioxidant that protects cell membranes from damage by free radicals. By quenching free radicals, and preventing the damage they cause, antioxidants help limit the inflammatory alarm to keep your immune response in proportion to the infection (8). 

Some cells of the immune system are always on patrol, like security guards. They can quickly respond to alarms going off and start fighting intruders. If your body has seen the intruder before, they call for back-up from the special forces immune cells that are much better equipped to neutralize the threat. Micronutrients are needed to support the functions of your immune cells; making immune cells, identifying foreign invaders, recruiting more immune cells to combat them and killing bacteria and viruses. Vitamin A, folate and vitamin B12 are needed to make new immune cells. Vitamin A and vitamin D help determine what types of immune cells your body makes so that you have the right cells to do the job when an infection hits (9,10).  Inside of immune cells, Zinc and vitamin E send signals that tells immune cells how to respond to an infection (11). Vitamin D helps immune cells make proteins that kill bacteria and viruses (10). Without these nutrients, your security team would be understaffed, asleep on the job and without the tools they need to fight intruders. 

Metabolism Support 

Metabolism describes how we convert food into energy and building blocks needed to grow and maintain tissues in your body. Metabolic pathways take a starting material through a series of reactions that make changes until a final product is made. This applies to both breaking molecules down to yield energy and using energy to build new molecules. Your body can break down carbohydrates, fats and proteins to access the chemical energy stored in these molecules to provide fuel for heat, transporting nutrients, contracting your muscles for movement and creating amino acids, fats, and DNA to build new cells. 

Metabolic reactions in the cell are done through the action of proteins called enzymes. Enzymes bring together molecules and break them down or combine them to make something new. Metabolic reactions are sped up with the help of vitamins, as coenzymes, and minerals, called cofactors. Thiamin (B1), riboflavin (B2), niacin (B3), pantothenic acid (B5), pyridoxine (B6) are examples of coenzymes that assist in the metabolism of carbohydrates, amino acids and fats. Iron, magnesium and manganese are cofactors that help your cells make energy.  

Bone Health 

Bones provide structure to your body, like the frame of a house. A healthy skeleton protects your internal organs, provides attachment points for muscles and tendons to allow movement and helps you stand upright.  

Your bones also serve as a reservoir of calcium. When calcium levels are low, bones break down to release calcium and when levels rise, calcium can be used to re-build bones. This constant remodeling of bones keeps your blood calcium levels consistent, even when you are not getting enough from your diet. 

Bone mineral density, how tightly the mineral crystals are packed into your bones, is a measure of bone strength. A lack of key bone-nutrients over time reduces the strength of your bones and increases the risk of fractures. 

Nutrients in Bone Health 

Your bones are made from minerals found in the foods you eat. Calcium and phosphorus are the most abundant minerals in your bones.  With the help of magnesium, fluoride and manganese, they form crystals that give your bones strength (12).  

Vitamin D enhances the absorption of calcium, phosphorus and magnesium. Vitamin D also conserves calcium when levels are low, by preventing calcium losses in the kidneys. Potassium also reduces calcium losses (13). Having an adequate supply of these minerals strengthens bones, as more minerals are deposited in the bone. 

Vitamin K assists in binding calcium to form bone and decreases bone turnover, this helps increase bone mineral density and reduces the risk of fractures (14). 

Blood Health 

Blood provides a vehicle to transport nutrients, wastes, hormones, and water around your body. Blood is made of red blood cells, white blood cells (immune cells) and plasma. The key roles of blood are to carry oxygen (in red blood cells) and nutrients (in plasma) to tissues and remove carbon dioxide and other wastes. Blood also carries immune cells that find and eliminate bacteria and viruses.  

Nutrients in Blood Health 

The nutrients in this group are involved in creating red blood cells that deliver oxygen to your tissues, or they are needed to form blood clots to stop blood loss when there is an injury.  

New blood cells are constantly being made to replenish your blood supply. Making new cells requires a supply of folate and vitamin B12. Red blood cells use a protein called hemoglobin to carry oxygen to your cells. Hemoglobin uses iron to hold the oxygen in blood and exchange it for carbon dioxide in your cells. 

Vitamin K and calcium are needed to repair injuries to blood vessels. Vitamin K makes proteins that allow your blood to clot to stop bleeding when blood vessels or other tissues are damaged. Calcium activates clotting proteins initiated by vitamin K. 

Oral Health 

These nutrients contribute to the health of your teeth and gums. Teeth help you tear solid foods into smaller pieces to help you digest nutrients in the foods you eat. 

Vitamin C is needed to make collagen that provides structure to cartilage and holds teeth in place. Vitamin C deficiency, called scurvy, causes bleeding around the gums and teeth become loose when cartilage breaks down.  

Sugar feeds bacteria in your mouth. They produce acid that erodes the enamel of your teeth. Without the outer protective layer, teeth are vulnerable to decay leading to cavities. Limiting sugar intake can reduce the rates of tooth decay. 

It’s not only the amount of sugar in your diet that is related to tooth decay. How long food stays in your mouth and how often sugar is consumed also have an effect. Stickier foods cling to teeth and are harder to brush away. Drinking water after eating helps clear sugars and staying hydrated ensures you can make saliva to help dilute and remove acids in your mouth. 

Fluoride provides extra protection in the hard enamel coating on teeth (15). It protects the mineral crystals from dissolving in acids produced by bacteria in your mouth (16). Teeth are formed from some of the same minerals as bone and nutrients in bone health are needed to maintain your teeth as well, including vitamin D, calcium and phosphorus. 

Keto Score

This score is designed to give you a look at how you are hitting your keto goals while reducing negative symptoms associated with a keto diet. This score is heavily weight towards meeting your target for total fat and staying under your limit for net carbs.

The Keto score is calculated from staying under your net carb limit, achieving your protein target without going over your maximum threshold, eating at least 4000 mg sodium, while meeting your targets for fat,  potassium, magnesium, water and fiber. Going over your net carb limit will rapidly reduce your keto score to zero since your body will be running on glucose from the carbohydrates instead of ketones. 

Keto flu can lead to headaches, nausea, brain fog and muscle cramps especially when starting a keto diet. You may feel better by drinking plenty of water and replenishing electrolytes lost while your body switches to burning ketones instead of glucose. If you are experiencing constipation, try drinking more water and increasing your fiber intake.

Plant-Based Score

With a little planning, you can get all the essential vitamins and minerals you need on a plant-based diet. This score shows whether you’re hitting some key nutrients that may be scarce in plant foods. Your score is calculated from achieving your daily target (without going over the max threshold) for: protein and the amino acid lysine, vitamin D, B12, calcium, zinc and omega-3. By default, the iron score uses 1.8 x your RDA as your target to account for lower availability of iron in plant foods. 

Women's Health Score

Men's Health Score

This nutrition score focuses on nutrients that tend to be lacking in men’s diets: fiber, vitamin A, vitamin D*, calcium and magnesium. Men generally have higher protein needs due to larger lean body mass. Meet your daily target for each of these nutrients to score 100%. Going over your max threshold for a nutrient will subtract from your total score. 

*Dietary intake is not the only source of vitamin D: we can make vitamin D in our skin through exposure to sunlight. Vitamin D from foods and supplements is more important for those with dark skin, or little exposure to sunlight, such as those who live in cloudy or northern climates. 

Data Quality

This score gives you a sense of how complete your data is. In other words, the proportion of foods you logged to your diary that have values reported for each of the nutrients that you are tracking. If the data nerd in you wants to learn more, check out our article on Data Confidence.

References 

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