FAD diets are everywhere; there is keto, carnivore, vegan, intermittent fasting, eat for your blood type, if it fits your macros, potato diet, juice diets, and the list goes on and on. As personal trainers and coaches, we must understand the pros and the cons of a restrictive diet so that we can support our clients with the information they need to make an educated decision on their diet.

Fad diets remove certain foods that cause inflammation, digestive issues and can impact our hormones. Restrictive diets are designed to promote certain foods based on certain nutrients and possible health benefits. Following these diets for a short period can have beneficial impacts on performance, health, and even longevity. However, there are some potential problems to be aware of when following a restrictive diet for an extended period.

Malnutrition - Sometimes, it can be hard to get enough calories or enough of specific nutrients from a particular diet due to the restrictions, particularly if you are physically active. Under-eating is a common problem on certain diets, and over an extended period, this can cause gut permeability, hormonal imbalances, insomnia, anxiety, and further health issues. As health and fitness professionals, we need to work closely with our clients and regularly check-in to see how they are responding to a particular diet.

There’s no one-size-fits-all approach when it comes to diet, and you would be foolish to think so.
Being too low-carb. Many carbohydrate-dense foods are pulled out of certain diets, or clients may go low-cab unknowingly. By removing processed foods like sugar and flour from the diet, clients often forget to increase there intake of starchy vegetables and fruits to replace the crap they were eating.

Diets such as Keto have very low-carb intakes, which can have catastrophic health implications for certain people, especially women, if not managed correctly. You need to make sure your client’s carbohydrate intake is matched to their activity level. The more glycolytic or powerful, explosive types of movements they are doing, such as certain types of weightlifting, martial arts training, CrossFit, or sports such as basketball or soccer, the higher their carbohydrate intake will likely need to be.

Carbs are not the energy they are made out to be, and far too often, we see uneducated trainers and exercise programs promoting high-intensity training on a low-carb diet.
Over restrictive. A client should rarely be on a 100% restrictive diet for more than 60 days. It is important to reintroduce foods and to take regular breaks from the diet. Hello, cheat days! Because of concerns around malnutrition and just the psychological effect of being on a very restricted diet for too long, it is a good idea to start reintroducing foods and not getting stuck on the very strict version of a particular diet.

If we take dairy as an example, presuming you can tolerate full-fat dairy products, dairy can be very healthy food. Dairy contains the fat-soluble vitamins A, D, and K2; minerals like calcium and phosphorus; trace elements; beneficial bacteria like Lactobacillus; long-chain saturated fat; and a natural trans fat called CLA.

If clients can tolerate dairy and its a healthy source of nutrients why should we restrict is if the client wants to include it?
Restrictive diets have the potential to create eating disorders and a fear of certain foods. There is a name for this fear of food, orthorexia, which is essentially a kind of addiction to being on a restricted diet. Any restrictive diet can trigger food fears over time. You always want to focus on the short-term nature of a strict diet with your clients and make sure that they are aware that many other lifestyle and behaviour factors such as stress are often as important, if not more important, than the diet. If a strict diet is stressful, which it will be for many people, and it also tends to limit their social activities, which in turn can be another stressor, we must consider broadening the diet to reduce the impacts of stress. Low levels of stress for a short period can be beneficial, but long term chronic stress is never a good idea.
Social isolation. Social isolation can be another potential issue with restrictive diets. We know that a lack of social support is a greater predictor of early death than smoking 15 cigarettes a day. Social support is very important to overall health, well-being, and healing. Unfortunately, a strict diet is nearly impossible to follow when eating outside of the home. This can lead to social isolation and people refusing to eat while they are away from home. As trainers, we must help clients learn how to navigate eating outside of the house and pack foods where possible.

Social eating and being able to socialise with friends outside of the house is a big reason why it is so important to reintroduce foods and not get stuck on a strict diet for an extended period.
Being overly focused on the diet as a key healing component. This is another risk of a strict long-term diet. Diet is only one part of an overall health plan, and in some cases, it may not even be the most important part. Strict diet on its own is unlikely to deliver the results our clients are looking for. We need to focus on things such as stress, sleep, movement, play, fun, and social connection just as much, if not more. We need to weigh up the pros and cons of following a strict diet and not let the strictness of the diet impair our ability to manage other lifestyle factors or engage in some of the other important aspects of healing.

There is a lot of misleading information in the health and fitness industry and everyone is trying to sell you something. We can listen to a podcast or read an article online that shares the story of someone losing a tone of weight, curing their chronic illness, increasing their energy or performance levels by following a certain diet or taking a certain superfood or supplement. This dose DOES NOT MEAN that this food or product will have the same effect on you, your clients, or anyone else.

There’s no one-size-fits-all approach when it comes to diet, and when we are working with clients that are dealing with a variety of health conditions, different lifestyles, activity levels, goals, health status, age, and gene expressions, we must be careful. Clients with severe blood sugar management problems, digestive problems, adrenal fatigue, hypothyroidism, and other health concerns can be made worse by cutting calories and following the wrong macronutrient percentage. Do you really want to take that risk?

Many personal trainers and coaches are only taught nutrition basics around calories and macronutrient ratios. This is simply not enough to be giving nutritional advice. As health and fitness professionals, we must learn more about nutrition if we truly want to be able to help our clients improve their health and longevity.

I hope you’ve enjoyed my post this week. If you have any questions, please let me know?

I coach ambitious, driven and committed health and fitness professionals (ADCHFP) who strive to juggle their health, career, peak performance, & personal life. As part of the Protect The Asset course I give trainers and coaches further nutritional tools that they can use to improve their own health, performance and longevity. They can also implement these tools with their clients.