A Personalized Functional Nutrition Approach to Weight Loss

January 15th, 2023

A Personalized Functional Nutrition Approach to Weight Loss

The start of a new year often means a renewed commitment to health goals and with almost 80 percent of Americans being overweight or obese, weight loss is often at the top of the list (1). The weight loss industry, estimated to be worth more than 72 billion dollars, includes many programs, supplements, and devices all promising to provide lasting weight loss. With so many options, why do Americans continue to gain weight at such a rapid pace?

In 2018, 42.4 percent of Americans self-reported obesity, representing a 39 percent increase since the year 2000. Even more alarming, one in five American kids are now obese (2). Turning the tide on this epidemic is not as simple as eating less and moving more. Of course, nutrition and exercise are crucial components of any successful weight loss plan, but obesity is a complex disease requiring a multifaceted strategy. Before diving into the best weight loss approach, let’s discuss what causes obesity.

What Causes Obesity?

Unfortunately, there is no one cause of obesity. Rather, a complicated interplay involving genetics, environment, and metabolism unfolds over time for each individual. Of course, eating patterns and physical inactivity are well-accepted as obesity contributors, however, there are several less-well known factors that can also underlie unwanted weight gain.

    • Genetics and Obesity. Genetic predisposition to obesity has been suspected for years, but with the advent of genome-wide association studies (GWAS), there have been numerous genes and gene variants found to be associated with overweight and obesity. For example, agouti-related protein (AGRP) acts as an endogenous antagonist of the melanocortin 4 receptor, which binds to increase food intake. And the leptin gene (LEP), which circulates in proportion to fat mass, stimulates the starvation response when its levels drop below a certain point. (3)In addition, those with the BMI-increasing allele of the fat mass and obesity-associated gene (FTO) single nucleotide polymorphisms (SNPs) tend to have increased appetite with reduced satiety, but also have less control over their intake and tend to make unhealthy food choices. In addition, they typically consume more calories and fat than those without this gene. It’s important to remember that genetic risk doesn’t always translate into actual obesity. For example, physically active patients with FTO have a 30 percent less risk of developing obesity when compared to their sedentary counterparts (4).


    • The Gut Microbiome and Obesity. When it comes to those who are overweight or obese, the gut microbiome is altered when compared to those of normal weight. The vast array of microbes in the gut may contribute to unwanted weight gain, in part, due to their ability to extract calories from foods that are normally indigestible to humans. The downstream results include inflammatory cytokines and metabolites that may affect metabolism. In addition, dysbiosis seems to be common, which can disrupt the gut barrier leading to increased intestinal permeability and alter the metabolites important for satiety and insulin signaling (5).Furthermore, emerging research on the brain-gut-microbiome (BGM) axis suggests food addiction is a complex disorder related to an imbalance in the signaling from gut to brain and from brain to gut. For example, early childhood experiences may shift the developing gut microbiome and brain to encourage food addiction. Additionally, the standard Western diet contains a limitless supply of addictive foods and beverages which alter the central nervous and gastrointestinal systems impacting a person’s food behavior (6).


    • Chronic Stress and Obesity. Hypothalamic-pituitary-adrenal axis (HPA-axis) function is altered in those who are overweight and obese, which can be both a cause and a consequence. During chronic stress, glucocorticoids like cortisol are continuously released ultimately leading to muscle and bone mass loss along with an increase in visceral fat accumulation. But as reported in Current Obesity Reports, the elevated cortisol levels seen in obese patients may also be the result of patient-specific variation in the enzymes responsible for cortisol metabolism or physical stressors such as inflammatory food and alcohol intake, chronic pain, and impaired sleep. Furthermore, pro-inflammatory cytokines like those common in obesity can influence the HPA-axis (7).


    • Sleep Deprivation and Obesity. Sleep and obesity seem to be closely tied whereas lack of restful sleep may contribute to weight gain but obesity itself affects sleep quality. Several potential mechanisms exist including sleep variability, which is associated with higher caloric intake and the increased consumption of sugar-sweetened beverages. Additionally, low sleep efficiency and quality can alter autonomic nervous system and HPA-axis function which may promote abdominal fat accumulation. Furthermore, obese patients tend to have altered sleep related to obesity complications including obstructive sleep apnea, depression, gastroesophageal reflux disease, joint pain, and asthma (8).


  • Toxins and Obesity. Endocrine organs and hormones such as insulin, glucagon, and estradiol work as a team to help control metabolism and weight. Endocrine disrupting chemicals, or obesogens, can actually affect hormone production, destruction, and transport, but also alter the function of hormone receptor sites. Bisphenol A (BPA) is the perfect example. It has been found to increase the mRNA expression and enzymatic activity of the enzyme that converts inactive cortisone to the active hormone cortisol in adipose tissue and promote adipogenesis, especially central obesity. While obesogens alone may not cause obesity, they are thought to alter the metabolic set point and the hormonal regulation of appetite and satiety to promote the development of obesity over time (9).


Creating a Personalized Weight Loss Plan

There’s no one-size-fits-all when it comes to weight loss. As you can see, weight gain can be the result of numerous factors, so a personalized functional nutrition approach to uncover and correct underlying dysfunction(s) in an individual patient is crucial.

In Track 2, Module 5, Kylene Bogden, MS, RDN, CSSD, CLT, IFNCP provides a variety of considerations for helping clients lose weight.  Kylene reiterates that personalization demands prioritizing each patients’ unique story and practitioners must be willing to dig well beyond dietary intake for stubborn weight gain.

The IFNA STAIN model provides a framework for practitioners to begin to investigate the root causes of unwanted weight gain. Using this model, practitioners can evaluate stress, toxins, adverse food reactions, infections, and nutritional factors that could be contributing to weight gain or prohibiting weight loss in a specific patient. In addition, Kylene recommends using the HANDS ON and MySQ IFNA tools to guide the creation of the nutrition care plan which should address food, lifestyle, labs, supplements, and resources/referrals.

Food for Weight Loss

There are many successful meal plan options for weight loss, everything from a Mediterranean to a ketogenic diet. The best therapeutic meal plan is the one that is personalized to the patient. Depending on root causes, many patients will benefit from some type of elimination diet initially. Kylene cautions practitioners to take care when prescribing elimination diets in order to prevent pushing patients into disordered eating tendencies. Practitioners should explain the rationale for the meal plan, that it is a temporary strategy for healing, and a maintenance meal plan will be prescribed in the future.

Kylene shares her weight loss meal plan pro-tips, which include adding in high-quality fats like olive oil and decreasing inflammatory omega-6 vegetable oils. High quality fats help to stabilize blood sugar, increase satiety, fuel the brain, support healthy hormone creation, and improve the metabolic landscape (10).  Kylene also recommends time-restricted eating (TRE), which has been shown to decrease body weight and fat mass while maintaining muscle mass, but also improves fasting blood sugar and blood pressure, upregulates autophagy, and decreases proinflammatory cytokines (11).

Nutrition professionals often get caught up in the meal planning aspect of weight loss, but Kylene reinforces the importance of personalizing the plan for the specific patient. If someone is not ready to make major nutrition-related changes, focusing on circadian entrainment and TRE can still be very effective strategies until the patient is ready for other food-related modifications.

Lifestyle Changes for Weight Loss

Lifestyle changes in the areas of sleep, movement, and stress are as important for weight loss as food-related changes.  Get to know current patterns and work with the individual to personalize goals in these areas.

  • Sleep. Alteration in the circadian system is thought to underlie obesity and light exposure and meal timing both affect metabolism (11). Creating routine sleep and wake times with no food consumption within three hours of bedtime and no blue light exposure within one hour of bedtime can be a great way to restore proper circadian function. Additionally, getting the person into natural light as soon as they awaken is also beneficial for resetting the circadian system (12).
  • Movement. Contrary to popular belief, hours and hours on cardio machines at the gym is not required for health or weight loss. A comprehensive exercise plan includes cardiovascular, strength training, and flexibility exercises. If someone is new to exercise, a simple ten-minute walk after every meal will help improve the post-prandial blood glucose and insulin responses (13). Once the individual has gotten more movement added to their day, encourage full-body strength training, which can increase lean body mass, reduce fat mass including visceral fat mass, and improve a variety of cardiometabolic parameters (14).
  • Stress Management. Kylene says stress management can save a life. Encouraging a simple daily stress management practice such as yoga or meditation may help decrease binge and emotional eating behaviors, which can lead to weight loss (15).

Labs for Weight Loss

Labs and functional tests are very helpful when determining the root causes of weight gain. Possible tests to consider include:

Conventional Functional
Comprehensive metabolic profile Organic Acids
Complete blood count Cardiometabolic Panel
Fasting insulin and hemoglobin A1c; Continuous Glucose Monitoring (CGM) Glucose Insulin Tolerance Test
Complete iron profile and ferritin Stool Studies
Complete thyroid panel including antibodies Food Sensitivity Testing
Celiac profile including HLA-DQ2 and HLA-DQ8 Adrenal Stress Index
Serum 25-OH vitamin D Nutrigenetic Panel
Red Blood Cell Magnesium
High Sensitivity C-Reactive Protein
Serum Fibrinogen
Advanced Cardiovascular Risk Profile


Supplements for Weight Loss

While food should be the foundation, dietary supplements can be very beneficial for weight loss.  Supplement recommendations should be tailored based on the root cause analysis, but a few supplements to consider for weight loss include:

  • Probiotics: have been shown to improve the metabolic profile in obese patients (16).
  • Whey Protein (100 to 600 grams per week) for those who tolerate dairy: can decrease appetite and maintain lean muscle mass (17).
  • Resveratrol (75 to 2,000 milligrams per day) and Green Tea (100 to 460 milligrams per day): Resveratrol mimics calorie restriction and both resveratrol and green tea increase lipolysis and reduce lipogenesis (18,19).
  • Conjugated Linoleic Acid (4 grams per day): As an addition to a nutrition and lifestyle-related program may promote weight and fat loss (20).

Resources/Referrals for Weight Loss

While nutrition professionals have many tools in the toolbox to help patients lose weight and heal, referring to specialists may be necessary. A functional medicine or naturopathic physician, certified personal trainer, and massage therapist can all contribute very successful strategies to the weight loss plan. In addition, practitioners should be mindful of the mental health aspect that often accompanies overweight and obesity. A trauma counselor may be the missing link.

Functional nutritionists are key to reversing the current obesity trend. To learn more about a functional nutrition approach to weight loss, register for your IFNA training today!

by Kellie Blake, RDN, LD, IFNCP


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