Ah the new year.  The time where every dietitian has to explain every diet out there and why it’s ridiculous.  So here is the good news, most diets work.  Breaking news: if you stick to a diet, you will lose weight.  If short term weight loss is your goal, the type of diet doesn’t matter as each diet or program has one thing in common: cutting back.  Cutting back/ restricting food will lead to weight loss. Yay!

But, before you start counting calories in hopes to cut 3500 in a week to drop one pound, listen up. The latest metabolic literature shows us that there is so much more than cutting 3500 calories per week. When you lose weight your body adapts, even if you don’t lose any lean body mass, your metabolism will slow down.  This means you need less calories to maintain your new weight and even fewer calories to lose more weight.  It’s not simple math.  I know….so frustrating!

Here is the 411 on the diet trends I get asked about the most:

Whole 30/Paleo

Have a friend that does Crossfit?  Or know a girl in college?  THEY LOVE THIS.  These diets are similar as they eliminate entire food groups which can be cause you to become deficient in calcium, iron, b vitamins, cutting out food groups, low in legumes (highest fiber food!).  The rules are easy to understand and socially this is a “in”.  But cutting grains, dairy and legumes; we know this is not evidence based.  A red flag should go up anytime an entire food group is “off limits”.

Detox diets and cleanses

Want to annoy a dietitian?  Mention these words.  You don’t need to detox or cleanse.  Your body does this for you thanks to your kidneys and liver!  This diet can be full of laxatives and diuretics so you are in the bathroom…a lot.  Juice cleanses are very high in sugar so this is a nightmare for someone who is diabetic or prediabetic.

If It Fits Your Macros “IIFYM”

Similar to carb counting or weight watchers, “IIFYM” diet is point counting.  You have to count and log so the diet does involves more thinking.  Lots of meal prepping and eat the same foods daily.  You lose weight on this diet as you are restricting calories.  Similar results to other diets.

Low fat

Grab your doc martin’s and put your choker necklace on…it’s time to channel the 1990s version of yourself!  In the 90s, fat was TERRIBLE.  This diet demonizes fat of any kind.  Red flags should go up any time a food group is demonized or eliminated.  Low fat usually means an increase in carbohydrate consumption.  Food companies took out the fat and replaced product with sugar.  Remember those green Snackwell boxes?!  Great news: fat is back!  While you want to limit saturated and trans fats, you want to consume healthy fats like monounsaturated and polyunsaturated fats (nuts, salmon, avocado, olive oil).  These healthy fats help with satiety, blood sugar control, cardiovascular disease prevention and more.

Low carb

Now, flash forward a decade…the 2000s: boy bands, Britney before her 2007 meltdown, you get the picture.  The diet breakdown is as follows: <40 % carb, 30% fat, 30% protein.  Compared to low fat diet, the low carb diet may lead to great weight loss in first 6 months.  But by 12 months, both the low fat diet and low carb diet yielded the same weight loss.  Best selling point with the low carb diet is the greater weight loss initially. Greater weight loss = better adherence = better success!  Carbs don’t make you fat, party people.  Who loves carbs?  THIS GIRL.

Intermittent fasting

This diet is easy.  You eat.  Then you don’t.  The diet has you limit all food for 4-8 hours of the day.  Research shows it is easier to cut calories on some day versus cutting calories daily.  Best part, no food is off limits!  Contrary to popular belief, we do not see folks over consuming calories on non-fasting days.  The belief is that diet participants are in better touch with their hunger cues.  There can be some not so lovely side effects.  Issues with fasting can include: gout, urinary stones, abnormal heart rhythm, and a drop in blood pressure.  Check with your doc before you do this.

Ketogenic Diet

Diet developed to treat epilepsy and seizures.  Like, why is this even a thing?  This diet is 80-90% fat, 15% protein and < 5% carbohydrate.  The diet consists of mayonnaise, heavy cream, fatty steak with green leafy vegetables (easy because there are very few choices).  YUM!  This diet is very socially difficult.  Obviously, it is not nutritionally sound which means it is low in key nutrients like fiber (side effect is constipation), calcium, vitamin d, iron, potassium and folic acid.  Common side effects are headaches, fatigue, bad breath, grouchy and leaky gut (loosen intestinal gaps in intestinal lining).  With all that being said, you did get immediate weight loss!  It’s all water as you are depleting your glycogen stores.  The second you stop this diet, you gain weight as you are reintroducing carbs back into your life.  Your cholesterol and LDL elevate and arteries stiffen which can affect blood pressure. I am still baffled that this is a thing these days.  Ew (in my Jimmy Fallon voice).

Long story short, all help you lose weight.  What do I tell my friends and family?

  • Don’t eliminate a food group
  • All foods can fit
  •  You HAVE to exercise (both cardio and strength training)
  • You have to watch your portion sizes
  • And of course, follow science, NOT TRENDS